Zoro Select Carriage Bolt M10-1.50 × 40 mm Class 4.6 Zinc Plated PK50

Zoro Select M10 Carriage Bolts

These metric carriage bolts have a 10 mm diameter with a 1.50 mm coarse thread pitch and a 40 mm overall length. They are supplied in a pack of 50 pieces and manufactured to DIN 603 from Class 4.6 steel with a zinc-plated finish. The round head measures 23.35 to 24.65 mm across and 5.38 mm high, with a square neck 10.58 mm wide and 6.60 mm deep to prevent rotation during tightening.

Class 4.6 tensile limit

The Class 4.6 grade provides a tensile strength of 58,000 psi, which sets the maximum clamping force these bolts can sustain before permanent deformation. This strength level suits general-purpose fastening in wood, metal brackets and light structural assemblies where high preload is not required. Over-torquing beyond the yield point will stretch the shank and reduce joint integrity, so torque values must respect the grade limit.

Square-neck anti-rotation

The square neck under the round head is the single feature that distinguishes a carriage bolt from a standard hex bolt. It locks into a square hole or bites into soft material so the bolt does not spin while the nut is tightened from the opposite side. If the mounting surface cannot accept a 10.58 mm square or the application requires tool-driven installation from the head side, a different fastener type is needed.