Length (L, L1):- 28 mm Diameter 1:- 16,1 mm Diameter 2:- 17,5 mm Depth of Head (a1, t):- 9,0 mm Width Across Flat:- 7/16 inch Drive Connector Square (Female):- 3/8 inch Packing Unit:- 1 Piece Weight:- 0.027 kg Drive Connector Square (Female) Nominal Size:- 10 mm