Skiff Made Blades make these bearings and they come in a set of two. Cage bearings like these give support to the blade as it flips and moves. The maintenance and installation processes are made more accessible because the the balls are held by a hardened race washer. Get these bearings to customize a knife or use them as replacement bearings! They are great knife accessories!
Knives that are compatible are the Flytanium Talisong Z, Kershaw (Butterfly), Koenig Arius, Koenig Mini Goblin, McNees Knives MAC2-3.5, Medford Slim Midi, Malibu, Spyderco Amalgam, Paysan, Smock, Tacticle Knife Rockwall, ZT 055, 0456.