316 Stainless Steel Tri Groove Nut Kit Includes #4, #6, #10, #20, #30 & #40 Tri Groove Socket Drivers 3/8" Drive 72 Teeth 8" Handle Pear Ratchet Handle with 3" Drive Extension Bar & 1/4" Drive Ratchet Adapter Marine Grade 316 Stainless Steel Tri Groove Nuts Contains 10 Pieces of each: 1/4"-20, 5/16"-18, 3/8"-16, 1/2"-13 The Complete Tri Groove Socket Kit with 316 Stainless Steel Nuts features Tri Groove Sockets in sizes #4 to #40 with accompanying Tri Groove Nuts. 316 Stainless Steel Tri Groove Nuts are highly corrosion resistant which adds to the benefits of tamper proof fasteners since they are suitable for long lasting outdoor applications.