Omega Technologies RR400SP Extra Heavy Duty Roller Ratchet®, 3/8” Square Drive were designed as a response for the need of small ratchet wrenches that could be used in tight areas where the swing of the handle was limited by obstructions, and to have a ratchet or tool that would work with very little handle movement. Roller Ratchets® satisfies both of those requirements and is used throughout the aerospace industry.