Hex Key Set Standard 10 PieceThe RTYKS1512 Javelin Hex Key Set Standard 10 Piece 1. 512mm is a standard hex key set covering sizes from 1. 5mm to 12mm. The set is intended for tightening and loosening hex socket fasteners during general maintenance, assembly, and workshop tasks. Suitable for mechanics, technicians, and general trades, this hex key set is designed for workshop and site use where a broad range of common hex sizes is required for everyday fastening applications.