Metallics UBS011 Bolts 5/16-18 X 2-3/16 X 1-3/8 U-Blt SS (Bag 10)

The UBS011 is 18-8 stainless steel, the standard 300-series austenitic grade used where plated or galvanized fasteners would rust out. That makes it suitable for exterior runs, rooftops, mechanical rooms, wash-down areas, and damp locations. For chloride-heavy coastal or pool environments, 316 stainless is the usual step up.

Two hex nuts ship with each U-bolt, so nothing extra is needed to make up the clamp. The nuts measure 0.489 to 0.500 inch across the flats and 0.258 to 0.273 inch high, built to ASTM F594 for stainless fasteners. If the job calls for a saddle or backing plate behind the pipe, that is a separate item.

Both ARRA and Buy American compliance are flagged on the UBS011, which is what a public-works or federally funded project specification usually asks for. Country of origin is listed as multiple, so if your contract requires a single named origin on the submittal, confirm the origin of the lot you receive.

Threads follow ANSI/ASME B1.1 at 18 threads per inch, right-hand, so they take any standard 5/16-18 stainless nut or coupling. Nut dimensions follow ASME B18.2.2 and the material conforms to ASTM F594. That combination is what lets an inspector or engineer sign off on the fastener against a drawing callout.

A U-bolt wraps the pipe and bolts through a flat surface, a drilled angle, a channel, or a backing plate, and it resists movement in every direction once both nuts are tightened. Use it where you have something you can drill through. If you are mounting to Unistrut or similar channel, a strut-style pipe clamp seats in the channel lip without drilling and is faster. The UBS011 covers electrical, plumbing, heating, and air conditioning work.

They are bagged 10 to a pack, and 10 each is the order minimum, so the smallest quantity you can buy is one bag of ten complete U-bolts with their nuts. Bag weight runs 535 g. For larger pipe-rack jobs, Metallics makes other sizes and pack quantities in the UBS series on request.