McGard lock nut set (4 nuts + 1 wrench). Open nuts with 1/2"-20 UNF thread. Order number for nut covers M70005 or M70006. Nut height 19.7 mm. Chuck diameter 28 mm. Wrench size 19/21 mm. Do not use a pneumatic wrench to tighten the lock nuts! Each package comes with an ID number. You can order a spare chuck using this code!