Plastic components and assemblies are used extensively by Aerospace, Automotive, Electronics, and Commercial Industries. Although the variety of plastic applications are endless, and design requirements are diverse, there is one common denominator: they all require reliable fastening solutions.

KATO Insert Collars are compression limiters designed to safeguard plastic components of an assembly. Compression loads generated from tightening forces cause plastic components to deform (compress) and/or crack under excessive loads. KATO Insert Collars protect the plastic parent material by absorbing and resisting excessive loads, thereby ensuring the integrity of the bolted assembly.


KATO Insert Collars are manufactured from high strength carbon steel (per ASTM A1008). A zinc-nickel with clear chromate plating is applied for exceptional corrosion resistance.

KATO compression limiters utilize Prism shaped impressions to provide superior pullout and retention capability when compared to plain tube, split seam, grooved, and even solid knurled designs. KATO offers custom designed impressions like Prism + Spiral Belt, Pyramid, and Pyramid (no taper) to meet application requirements.

Examples of Custom Impression
prism prism prism prism
Prism + Spiral Belt
Pyramid (no taper)
Resin Material PBT (GF 30%) PBT (GF 30%) PBT (GF 30%) PBT (GF 30%)
Pull out Force 1,174.8 lbf (532.9 kg) 983.3 lbf (446.0 kg) 624.3 lbf (283.2 kg) 762.7 lbf (346.0 kg)
176.3 in-lb (19.92 Nm) 114.5 in-lb (12.94 Nm) 94.0 in-lb (10.63 Nm) 120.5 in-lb (13.62 Nm)

Features and Benefits

  • Prevents damage to parent material.
  • Designed for molded-in applications.
  • Superior retention and anti-rotational characteristics.
  • Lower Cost than solid tube and knurled limiters.
  • Custom designed for your application.
Example 2
Example 3

How Do KATO Insert Collars Work


When a bolt in an assembly is tightened the plastic parent material compresses. Stresses in the plastic increase until the head of the bolt or washer comes in contact with the compression limiter. Further tightening of the bolt will cause the the compression limiter and plastic parent material to compress at the same rate. KATO Insert Collars absorb the additional clamping loads without further significant compression or increased stresses in the plastic parent material.

The prism shaped impressions in KATO compression limiters prevents movement of the assembled components, and provides significant resistance to torsional and push-out/pull-out forces.

Environmentally Friendly & Lower Cost Manufacturing

Threaded Limiters

KATO Insert Collars are manufactured using highly advanced precision stamping and coiling processes developed by Advanex. This process offers manufacturing and cost benefits when compared to solid tube and knurled compression limiters. No machining is performed on KATO Insert Collars, so there's minimal or zero material scrap, no chips, and no oil residue. Fast, clean, and FOD Free!