Metallics JMHTB316 Bolts M3 x 16 C8.8 Hx Tap Blt St-zn (Jar 100)

It is an M3 bolt with a 0.5 mm metric thread pitch, right hand, and the thread runs the full length of the shank right up to under the head. That is what makes it a tap bolt rather than a partially threaded hex cap screw, so it works in tapped holes of any depth and in through-holes where you want full thread engagement. Length is 16 mm.

Class 8.8 is the common metric medium-carbon, heat-treated structural grade, roughly equivalent to SAE Grade 5 in inch sizing. The JMHTB316 is made from medium carbon steel, heat treated, and tests at Rockwell C22-32. Mounting a motor to machinery is exactly the application Metallics lists for this bolt, along with automotive and truck repair work.

No. These M3 x 16 hex tap bolts are not Buy American compliant and are not ARRA compliant, with multiple countries of origin. For federally funded work carrying domestic sourcing requirements, you will need a domestically produced fastener instead.

They ship in a jar of 100 pieces, and the jar is the order minimum, so 100 is the smallest quantity. Net weight of the jar is 127 g. Metallics notes other sizes and quantities are available by request if you need a different count or length.

The finish on this bolt is zinc plating over steel, which is a mild corrosion barrier meant for dry indoor and protected service. It is not a stainless or hot-dip galvanized fastener, so for wet exteriors, rooftop equipment, or anything washed down regularly, step up to stainless or hot-dip galvanized hardware instead.

No. The JMHTB316 is a metric M3 x 0.5 thread, which will not run into an inch-series tapped hole like 4-40 or 6-32, and forcing it strips the threads. Match metric to metric. If your equipment is imported machinery or a motor frame, metric M3 is usually what the tapped hole is cut for.

An M3 hex head takes a 5.5 mm wrench or socket under the standard metric pattern. There is a washer face under the head on this bolt, so it seats flat on a finished surface without a separate flat washer, though you will still want one over soft material or oversized holes.

Metallics targets this one at electrical, plumbing, heating, and air conditioning work, where small metric hex bolts get used to fasten equipment, motors, panels, and brackets to tapped frames. It is also commonly pulled for automotive and truck repair. At M3 it is a small-diameter fastener, so for structural steel or anchoring you want a larger diameter.