Metallics JMHTB8201 Bolts M8 X 20 C10.9 Hx Tap Blt St-zn (Jar 100)

Yes. The JMHTB8201 is a hex tap bolt, meaning the thread runs the full length of the 20mm shank right up to underneath the head. There is no unthreaded grip section, so it works where you need thread engagement through the entire clamped stack or where you are running into a tapped hole of unknown depth.

It is a 1.25mm pitch, right hand thread, which is the standard coarse pitch for M8. It will thread into any standard M8 x 1.25 coarse tapped hole or nut. If your equipment uses M8 x 1.0 fine thread, this is not the bolt for it.

Class 10.9 is the higher strength option. This Metallics bolt is grade 10.9 with a minimum tensile strength of 150,800 psi and minimum yield of 136,300 psi, hardened to Rockwell C32-39. Metallics specifies it for automotive and fleet work where a class 8.8 fastener does not give enough tensile strength. For general bracket and strut work an 8.8 is usually sufficient; step up to 10.9 when the engineer or the equipment manual calls out the higher class.

The JMHTB8201 ships as a jar of 100 bolts, and the jar is the minimum order unit. The filled jar weighs 1352 g. Metallics does make other sizes and quantities in the MHTB and JMHTB tap bolt series available by request.

These are steel bolts with a zinc finish. Zinc plating is a light sacrificial coating suited to indoor and protected locations, mechanical rooms, panel and equipment mounting. For sustained wet exposure, coastal air, or direct burial, go with hot dip galvanized or stainless instead. Keep in mind stainless will not give you class 10.9 strength.

No. These bolts are not Buy American compliant and are not ARRA compliant, with country of origin listed as multiple. On federally funded or domestic preference jobs you will need a domestically sourced fastener instead.

Metallics lists it for electrical, plumbing, heating and air conditioning work. In practice that is equipment and panel mounting, strut and bracket connections, and fastening into tapped holes on mechanical gear where the manufacturer calls for an M8 metric fastener rather than an inch size.

Not necessarily. The hex head has an integral washer face underneath it, which spreads the bearing load against the mounted part. On soft materials, slotted strut, or oversized clearance holes you should still add a flat washer; on a flat machined face the washer face is generally enough.