Metric Bolts

Metric Carriage Bolts have a low-height round head, a square neck under the head and coarse machine screw threads. Since the head is designed to not turn, tighten using a nut to fasten wood to wood, wood to metal and metal to metal. They are also known as Carriage Screws, Coach Bolts and, when fully threaded, Shaker Screen Bolts.

Metric Flange Bolts are hex washer head bolts with coarse machine screw threads. A round flange that is larger in diameter than the width of the hex head creates a large bearing surface that spans irregular and oversized holes. Supplied with a smooth underhead bearing surface, they are also known as Flange Screws and Frame Bolts and are often mated with Flange Nuts.

Metric Hex Head Bolts have a hex head and coarse and fine machine screw threads and are one of the most common bolts available. Longer lengths are partially threaded. Hex Head Bolts are the same as Hex Bolts, Machine Bolts and their name is used interchangeably with Hex Head Cap Screws and sometimes Tap Bolts, both of which are fully threaded.

Metric Machine Bolts are also known as Hex Head Bolts and have a hex head and either coarse or fine machine screw threads. Short lengths are fully threaded while long lengths are partially threaded. The name Machine Bolt can also refer to Hex Bolts, Hex Head Cap Screws and Tap Bolts (the latter two are fully threaded).

Metric Shoulder Bolts have a precisely-sized cylindrical shoulder and, when compared to the shoulder, a larger diameter cylindrical hex socket head and a smaller diameter short tip with coarse machine screw threads. They are used as bearings, guides, shafts and pivots. They are also known as Axle Bolts and Stripper Bolts.

Metric Tap Bolts are essentially Hex Head Bolts. They have the same hex head and coarse and fine machine screw threads, but all lengths are fully threaded. They differ from tapping screws (sheet metal screws) because they are not designed to cut or form mating threads. Their name also applies to fully threaded Hex Head Cap Screws.