Ck hexagon keys ck tools t4443m manufactured from chrome vanadium steel hardened and tempered for strength and durability ball ended for use at an angle of up to 25o where access is restricted set is supplied in a clip holder for convenient storage and contains sizes 15 2 25 3 4 5 6 7 8 amp 10mm ck tools t4443m ball end hexagon key metric set of 10