Bearings with a 3/16" inner diameter are placed at the stub end of the router bit and come very handy for rabbeting applications.

Bearings with an inner diameter of 5/16" are placed among other blades and hardware stacked on the router bit's arbor. They can replace original bearings or be used to alter the cutting depth of various bits.

Bearings with an inner diameter of 1/4" are placed on the shanks of router bits with 1/4" shank diameters and secured to the shank with a metal collar or sleeve. Choose an outer diameter that matches the cutting diameter of your bit or you can combine with various cutting diameters to create some interesting flush trim configurations.

Bearings with an inner diameter of 1/2" are placed on the shanks of router bits with 1/2" shank diameters and secured to the shank with a metal collar or sleeve. Choose an outer diameter that matches the cutting diameter of your bit or you can combine with various cutting diameters to create some interesting flush trim configurations.