US PRO INDUSTRIAL Impact Spline Bit Sockets Tamper Proof Spline 1/2" M4-M18 3435
M14 - M16 - M18. M4 - M5 - M6 - M8 - M9 - M10 - M12. IMPACT SPLINE BIT SOCKET SET. ALL SOCKETS ARE 1/2" DRIVE (55mm LONG ) US.PRO INDUSTRIAL. Each Socket Has A Drilled End To Facilitate Retaining Ball Bearing For Use.