Metallics TS225M 8 x 1-1/4 in. Pan Head Phillips Sharp Point Tapping Screws - Steel Zinc - Each

The TS225M has a gimlet (sharp) point, so it starts on its own in thin sheet metal and forms its own thread as it drives. It is a Type A tapping screw, which is the coarse-thread sheet metal screw at 15 threads per inch. In heavier gauge steel or in hardwood you still want a pilot hole sized to the screw's root diameter, but for sheet metal boxes, straps, and duct work the sharp point is the whole point of this screw.

They ship as a box with a 5,000 piece order minimum. That box weighs 29.89 lbs. If you need a smaller count for a punch list, this is not the pack for it; it is priced and packed as a shop or truck stock quantity.

The TS225M is flagged compliant for both Buy American and ARRA. Country of origin is listed as multiple, so if your contract requires a single documented origin per lot, request the certification for the specific lot you are receiving.

A #2 Phillips. The recess on the TS225M measures 0.169 to 0.182 in. diameter with a 0.108 in. depth, which is the standard #2 Phillips geometry. Running a #1 will cam out and a #3 will not seat.

Minimum torsional strength on the TS225M is 39 lb-in, with the screw heat treated to Rockwell C28-38 and made from AISI 1016-1024 steel. That is enough to drive through sheet metal with an impact or clutch driver, but set a cordless driver's clutch rather than running it wide open, since 39 lb-in is well inside what a modern impact can deliver.

The TS225M is steel with a zinc plated finish, which is a mild indoor corrosion coating. It is fine for dry interior work, electrical rooms, and enclosed boxes. For exterior exposure, wet locations, coastal air, or treated lumber contact, go to a stainless or hot dip galvanized fastener instead, since plated zinc will bloom and then rust.

No. A Type A screw like the TS225M has a gimlet point that pierces and forms a thread, but it has no drill flute, so it will not cut through heavier gauge steel on its own. A self-drilling screw has a drill tip that bores the hole first. Use the Type A for thin sheet metal, boxes, straps, and soft materials where the point can punch through; use a self-drilling screw for structural studs and thicker steel.

Threads follow ASME B18.6.4 at 15 threads per inch, with head dimensions to ASME B18.6.3-2013. That means the TS225M interchanges with any other standard #8 Type A sheet metal screw of the same length, so it drops into existing tapped holes from a prior #8 Type A screw.