Banding clips, seals and buckles: how each part holds the strap

There are three parts that close a strap: a seal for PP strap, a clip for steel strap and a wire buckle for textile or composite strap. The seal is crimped by a tool, the clip is crimped by a sealer and the buckle locks under the tension of the strap. Each part matches a specific strap type and width.

Where the tool makes the joint itself, no part is needed. Battery and pneumatic tools for PET and PP strap weld the joint by friction. Sealless steel tools such as BO-51, A3 and A4 interlock the steel strap, so no banding clips or seals are required.

Each of these three parts is made for a specific strap type and cannot be swapped between them.

Seals and clips both work by being crimped around the two overlapping ends of the strap. The tool or sealer presses the metal tightly, locking the strap in place. In contrast, a wire buckle is not crimped. Instead, you thread the strap through the buckle and use a tensioner to pull it tight. The tension in the strap keeps the buckle locked.

It is critical that every part matches the strap width. If you use a seal or clip that is too wide for the strap, it will not grip and the joint can slip under load. If the part is too narrow, it does not close. For example, a 16 mm steel clip will not hold a 19 mm steel strap. Always check the strap width before loading the tool, especially when switching between different products or sizes during a shift.

Textile strap gives you the option to tie a knot instead of using a buckle, but composite strap always needs a buckle for the joint.

When making a crimped joint with a seal or clip, the two ends of the strap must overlap inside the part and lie flat and straight on each other. If one end is twisted or not aligned, the seal or clip does not fill properly and the joint can slip under load.

Metal seals for PP strap: sizes and tools

Metal seals for PP strap are made of galvanised steel and come in 13 mm for PP strap 12–13 mm and 16 mm for PP strap 15–16 mm. Each unit contains 1000 metal strapping seals. The seal is crimped with the manual PPST-13/16 tool. For plastic strapping with battery or pneumatic tools, no seal is needed as these tools weld the joint.

Always match the seal size to the PP strap width. These seals are for PP strap only; tools that weld PET and PP strap by friction need no seals.

The manual PPST-13/16 tool is used to tension the PP strap, crimp the seal and cut the strap in one sequence. This tool does not require any power or compressed air, making it suitable for areas without access to utilities.

You use one seal for every joint you make. For example, if you strap a pallet with four straps, you need four seals. This means you should count seals the same way you count straps when planning your orders. The PP strap and the battery and pneumatic tools for PET and PP strap are sold under plastic strapping.

On the PPST-13/16 tool, you place the seal on the strap before tensioning. The process starts by clamping the strap end under the press-strap handle, then running the strap around the load and into the tensioning spindle. A seal is put on the overlap at this stage. You swing the tension handle until the strap is tight, then press the grip handle to crimp the seal and cut the strap in one movement.

These metal seals are not suitable for steel strap, which takes the steel clips of this category.

Product table: strapping seals, clips and buckles

The table below lists the four products in this category. It shows the strap type, available sizes, pieces in a box and the tool that closes each part.

To use the table, first identify the type of strap you use: PP, steel, textile or composite. Next, check the width of your strap, as each part is made for a specific width. Then, find the matching part and see which tool is needed to close it. The number of pieces in a box varies by part and width, so you should order based on the number of joints you make, not just by the box. For example, if you use 19 mm composite strap, look for the wire buckle for 19 mm and the correct tensioner.

Strapping clips for steel strap: manual and pneumatic

Clips for steel strap are available as manual steel clips 16 x 40 mm and pneumatic steel clips in 16 x 40, 19 x 57, 25 x 57 and 32 x 57 mm. Manual steel clips are packed 1000 in a box. Pneumatic steel clips come 1000 in a box, except the 32 x 57 mm size which has 800. All steel strapping clips are single use and are cut off with the strap.

The AIR Metal tool for steel strapping makes its joint with a clip. Sealless steel tools such as BO-51, A3 and A4 interlock the strap and do not require any strapping clips.

Manual steel clips are sized 16 x 40 mm and are made for steel strap 16 mm wide. They are used with a manual tensioner and a sealer that crimps the clip around the two overlapping strap ends.

Pneumatic steel clips are available in 16 x 40, 19 x 57, 25 x 57 and 32 x 57 mm sizes, matching steel strap widths of 16, 19, 25 and 32 mm. These clips are made of high-strength carbon steel for the pull of a pneumatic tensioner.

The AIR Metal is a pneumatic tool for steel strap 19–32 mm wide.

Steel strap and the tools for it are found under steel strapping, not in this category.

There are two types of 16 x 40 mm clips: one for manual strapping and one for pneumatic strapping. The manual steel clips are not made for powered tools, while the pneumatic steel clips are designed for the higher sealing force of pneumatic tools. Order the clip made for your sealer.

To make a joint with manual steel clips, the strap goes around the load and through the manual tensioner, where it is tensioned. You then place the clip over the overlapping ends of the strap. The manual sealer crimps the clip, and the rest of the strap is cut with the tool’s cutter or a separate cutter. On a pneumatic tensioner and sealer for steel strap 19, 25 or 32 mm, the strap is threaded through the clip, around the load and back through the clip, with the end bent back about 50 mm. The pneumatic tensioner pulls the strap tight, the sealer is set on the clip and forms the joint, then it is tilted up to cut the strap. Pneumatic clips fit most pneumatic steel tools made for the same strap width, and manual clips fit standard manual sealers for 16 mm steel strap.

Wire buckles for textile and composite strap

Wire buckles are used with textile and composite (cord) strap in widths of 16, 19, 25 or 32 mm. The wire is 3.5 mm for 16 mm strap, 4.0 mm for 19 mm and 5.0 mm for 25 mm. Packs contain 1000 buckles for 16 and 19 mm, 500 for 25 mm and 250 for 32 mm.

The strap is threaded through the buckle and tensioned with a manual tensioner for textile and composite strap. The buckle locks under the tension, with no crimping or sealing. Manual tensioners are available for 13–19 mm, 19–25 mm and up to 50 mm strap. Wire buckles are suitable for cord strapping.

The buckles are made of galvanised steel wire.

Composite (cord) strap, textile strap and the manual tensioners are found under cord strapping, not in this category.

The tensioner depends on the buckle width: 16 mm buckles are used with the 13-19 mm manual tensioner, while 19 mm buckles can be used with either the 13-19 mm or 19-25 mm tensioner. For wider straps, 25 mm buckles go with the 19-25 mm tensioner or the one for strap up to 50 mm, and 32 mm buckles are used with the same tensioner for strap up to 50 mm. The battery tensioner for strap 16-40 mm, found under cord strapping, works with all four buckle widths.

There is no 13 mm buckle, even though cord strap is available in 13 mm width. If you plan to use 13 mm cord strap, decide how to close the joint before ordering.

The buckle must be put on the strap the right way around before tensioning, because its grip depends on the orientation. When tensioning, stop once the buckle has closed on the strap from both sides. Applying more tension after this point can strip the strap. The cord strapping kit under pallet strapping kits comes with 1000 buckles for 16 mm strap, a manual tensioner 13-19 mm and two coils of 16 mm cord strap.

Why the joint matters

The joint made by strapping seals, clips or buckles keeps the tension that the tool puts into the strap. If the seal or clip is crimped on a loose strap, the joint slips and does not hold the load, however well it is crimped.

Each part must match the strap width. A part that does not match the strap width will not hold: too wide and it does not grip, too narrow and it does not close. A crimped joint is checked by eye: the notches must be even on both sides of the seal or clip. Worn sealer jaws leave shallow notches and a joint that opens under load.

Check the notches on the first joint of every shift. Replace worn jaws before continuing.

The placement of the joint on the load affects how well it holds. Always put the seal, clip or buckle on a flat face of the load, not over a corner. If a part is bent over an edge, it does not sit square on the strap and the joint holds less.

For buckle joints, a visual check is just as important as for crimped joints. The strap must lie flat in the buckle, and the buckle should have closed and sit square on the strap. If the buckle has turned sideways, the strap can slip through under load.

At the start of each shift, after making the first strapped load, pull the strap by hand next to the joint. The seal, clip or buckle must not move on the strap. If the joint moves, check the tool settings, the part size and the way the joint was made before continuing with more loads.

Storing and handling seals, clips and buckles

Strapping seals, clips and buckles must be stored dry and indoors. Bare steel rusts, and a rusted clip is harder to crimp and can mark the goods. All steel clips are single use: once crimped, they are cut off with the strap and cannot be reused.

When cutting a tensioned steel strap, the strap can spring back and its edges are sharp. Always cut with a strap cutter, wear gloves and eye protection, and stand to the side. This applies to every tensioned steel strap, whether it is closed with a clip or sealless.

Keep the open box of parts at the strapping station during use, but close it between shifts. This keeps the parts clean and prevents dust or debris from getting into the box.

Keep each width of seal, clip or buckle in its own labeled box at the strapping station. This prevents a 16 mm part from being used on 19 mm strap by mistake.

Before use, check each part for damage. A bent buckle or a deformed seal or clip should be put aside for scrap, not used in a joint.

Keep the PPST-13/16 and the manual tensioners for textile and composite strap clean, and oil their moving parts from time to time. Used steel clips and cut steel strap should be collected and sent to scrap metal recycling.

What affects the cost of strapping seals and clips

The cost depends on the number of joints (one part per joint), the pack size and the strap. If you use a tool that welds or interlocks the strap, such as a battery or pneumatic tool for PET and PP strap or a sealless steel tool, no strapping seals, clips or buckles are needed. The price for each product is shown on its card.

The cost per joint is one seal, clip or buckle. The pack size tells you how often you need to reorder: 1000, 800, 500 or 250 pieces, depending on the part and the strap width.

Each product card has a Get offer button for a quote, for example if you want to order clips together with steel strap, and an Add to inquiry button that lets you collect several products into one request.

If you buy a pallet strapping kit with the PPST-13/16 tool, the kit comes with its first metal seals, so you buy your first box of seals later.

What to check before ordering strapping seals

Before ordering strapping seals, check which strap you use: PP, steel, textile or composite. The part must match the strap type and width.

Check which tool closes the joint. PP strap seals are crimped with the manual PPST-13/16. Manual steel clips need a manual tensioner and a sealer. Pneumatic steel clips are for pneumatic tensioners and sealers such as AIR Metal. Buckles are tensioned with manual tensioners for textile and composite strap.

Count the number of joints you make by multiplying the number of straps per load by the number of loads per week.

Round up your order to full boxes based on your weekly usage.

When reordering, always match the seal to the width of the PP strap you are using, not just the name of a kit. For example, 12 mm strap takes 13 mm seals and 15.5 mm strap takes 16 mm seals, even if the strap came in a pallet strapping kit.

Measure the width on a piece of the strap itself, not from an old box or from memory. The width of the strap decides which part you need.

Check the width range of your tool as well. For example, a pneumatic tensioner and sealer for steel strap 19, 25 or 32 mm takes the 19 x 57, 25 x 57 or 32 x 57 mm clips, not the 16 x 40 mm clip.

Questions about strapping seals

Which strapping seals fit PP strap?

Use metal seals for PP strap in 13 mm for PP 12–13 mm and 16 mm for PP 15–16 mm. Each unit contains 1000 seals and they are crimped with the manual PPST-13/16 tool.

Does a battery tool for PET or PP strap need seals?

No, battery and pneumatic tools for PET and PP strap weld the joint by friction. They do not require any strapping seals or clips.

Which clips does a pneumatic steel strapping tool use?

Pneumatic steel clips come in 16 x 40, 19 x 57, 25 x 57 and 32 x 57 mm for steel strap 16, 19, 25 and 32 mm wide; the clip must match the strap width. The AIR Metal, a pneumatic tool for steel strap 19–32 mm, makes its joint with such a clip.

What holds composite strap in place?

Composite strap is held by a wire buckle. The strap is threaded through the buckle and tensioned, and the buckle locks under the tension. No crimping is needed.