Makita 763419-1 Chuck Key 10, 3/8 Inch Genuine OEM Makita Part Fits Various Makita Cordless Drill Models Including: 6012HD, 6093D, 6041D, 6170D 3/8", M001 3/8" The Chuck Key Is Designed To Tighten And Loosen The Chuck Jaws Made From High Quality Metal