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Cheat Sheet
Test Fit Card


Regular price $14.99

Not sure what size bearing or pivot a knife uses?

Use the Test Fit Card as a cheat sheet to quickly determine knife pivot size and bearing ball size. Simply insert the cage bearing or pivot barrel from the knife into the different sized slots and holes to figure out which their sizes. 

The Test Fit Card is machined from 6061 aluminum and the engravings are filled with enamel paint.


1.75" wide x 2.75" long x 0.100" thick

Test for the following sizes

Bearing sizes: 3/32", 1/16", 3/64" (1.2mm), 1mm and 2mm

Pivot sizes: 1/8", 3/16", 1/4", 4mm, 5mm, 6mm

Instructions for use

Find Pivot Size: Starting with the smallest hole, attempt to insert the pivot barrel into each hole until the barrel is able to pass through the hole.

Find Bearing Size: Starting with the smallest slot, attempt to insert the cage bearing through each slot until the bearing is able to pass through the slot. 

Customer Reviews

Based on 25 reviews
John Polsinelli

Love it

Jake @CanadianCuttingEdge
Fast and easy way to measure your bearings

There wasn't room on the card to measure the outside diameter, but if there was this thing would get a 10 out of 5.

Mark Prentice
The Cheat Sheet is Great!

The cheat sheet allows me to correctly identify bearing sizes for knife bearings that I'm unsure of the size. Great simple tool!!

Know your size

This lets you know exactly what size you need.

Gabriel Lopez
Cheat sheet

Very good