OGV profile socket design means more torque than a standard socket as there is a larger contact area between socket and fastenerOGV profile also means less wear on the fastener and the ratchet as torque is transmitted through the fastener flats instead of the cornersOGV profile also means less chance of rounding the fastenerLifetime warranty on partsSet contains:1 x 1/4 inch 'Hand-palm' ratchet - R.16110 x 1/4 inch 6-point metric sockets : R.05.5 - 06 - 07 - 08 - 09 - 10 - 11 - 12 - 13 - 14mm21 x 1/4 inch series 1 bits - L 25mmSeries 1 bits:ED.1T High Perf bit for Pozidriv screws : PZ1 - PZ2 - PZ3EH.1 - Standard bit for hex countersunk screws - metric : 3.0 - 4.0 - 5.0 - 6.0 - 7.0EP.1T - High Perf bit for Phillips screws : PH1 - PH2 - PH3ES.1T - High Perf bit for slotted head screws : F4.5 - F6.5 - F8.0EXR.1 - Standard for Resistorx screws : TT 10 - TT 15 - TT 20 - TT 25 - TT 27 - TT 30 - TT 401 x 1/4 inch socket holder bit - ECR1 x 1/4 inch Universal joint - R.240A1 x 1/4 inch bit holder socket with standard locking pin - R.2351 x 1/4 inch short screwdriver handle - R.236C2 x 1/4 inch standard extension L 55 mm - L 100mmWarning:Chrome sockets and adaptors should only be used with hand operated handles and ratchets