Metallics TP132SBC Screws 5/16-18 x 1-1/2 Btn Hx Pin TR (100 pcs)

The TP132SBC is a 5/16-18 x 1-1/2 inch screw with a button head and a hex pin tamper resistant drive. 5/16-18 is the coarse (UNC) thread pitch for 5/16 inch diameter, so it mates with standard 5/16-18 nuts and tapped holes. Sold 100 pieces to the box.

Yes. The hex pin drive has a post in the center of the hex recess, so a standard hex/Allen key will not seat. You need a pin-in-hex bit or key sized to match, with a hole bored down the center to clear the pin. That is the whole point of the head style: once it is installed, nobody with an ordinary hex set is backing it out. Order the matching driver along with the screws if your crew does not already carry them.

It is a common pick there. The button head sits low and rounded rather than projecting like a hex cap, so it is less of a snag point on covers, panels, and guards, and the pin-in-hex recess keeps casual tampering out of boxes in corridors, stairwells, transit areas, and tenant common space. If you only need clamping strength and the fastener is behind a locked door, a plain hex or socket cap screw is simpler and the driver is already in the bag. Where you want the fastener flush into the surface instead of proud of it, a flat head tamper resistant screw is the better form.

Each box of TP132SBC is 100 pieces of the 5/16-18 x 1-1/2 inch button head hex pin screw. For MRO stock that is usually a sensible shelf quantity, since tamper resistant fasteners get consumed slowly but you want the full set on hand whenever a cover comes off. Note that the 100-piece box contains screws only; nuts, washers, and the pin-in-hex driver are separate items.

The manufacturer part number is TP132SBC from Metallics. Quote that number when you are matching a previous order, since the TP series covers many thread and length combinations and the suffix is what pins down the 5/16-18 x 1-1/2 button head hex pin version.