33 Piece Set. Chrome Vanadium, multipurpose Security Bit Set. Compatible with most current tamper-proof fasteners. 33 Piece Set. Chrome Vanadium, multipurpose Security Bit Set. Compatible with most current tamper-proof fasteners. Magnetic bit holder, Torx set bits, spanner bits, tri-wing bits, hex bits and tamper-proof star bits. Security Bit Set 33Pc