Length (L, L1):- 28 mm Diameter 1:- 18,1 mm Diameter 2:- 19,2 mm Depth of Head (a1, t):- 9,0 mm Width Across Flat:- 1/2 inch Drive Connector Square (Female):- 3/8 inch Packing Unit:- 1 Piece Weight:- 0.034 kg Drive Connector Square (Female) Nominal Size:- 10 mm