fits large bearing YoYoJam yo-yos, including Hitman, Lyn Fury, Spinmaster, Big Ben, Journey, Patriot, Nightmoves, Shockwave, Speeder, as well as YoYoFactory G5, 888, Skyline, Grind Machine.
bearing model: R188ZZ—1/4″*1/2″*3/16″
bearing shape: flat and konkave
Dif-E-Yo Konkave Bearing Size C is the mega popular konkave bearing made by Frank Difeo. The outer surface is not flat, but slightly concave, there is a groove on outer ring that centers the string.