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Carlisle HP-XTRA #21 Steel Roof Fasteners, Mill, 2 in. to 12 in., 250 or 500 per Box
Regular price $355.00Orders start at $399 — combine any items to reach the minimum. Learn more
Carlisle HP-XTRA #21 Steel Roof Fasteners, Mill, 2 in. to 12 in., 250 or 500 per Box
Carlisle HP-XTRA Fasteners are #21 steel-threaded fasteners used with PIRANHA XTRA Fastening Plates to secure mechanically fastened Sure-Weld roofing systems to 22-gauge steel decks. Deep buttress threads at 13 per inch and a mini drill point deliver strong pullout and back-out resistance. Sold in boxes of 250 (7 in. to 12 in.) or 500 (2 in.).
Key Features:
- High pullout: Typical pullout values of 900 pounds are achieved in 22-gauge Grade E steel deck.
- Buttress threads: Deep buttress threads at 13 threads per inch put a flatter, wider surface against the deck bottom, increasing pullout and back-out resistance.
- Mini drill point: Cuts a hole in the steel deck while maintaining contact between the deck and the fastener's minor diameter for increased back-out resistance.
- Corrosion protection: Black epoxy electro-deposition coating surpasses the FM 4470 corrosion test of less than 15% red rust after 15 Kesternich cycles.
- Oversized truss head: Oversized truss head with #3 Phillips drive for secure driving.
- Bit included: One #3 Phillips screwdriver bit is included in each bucket.
- FM uplift: Enhanced Factory Mutual uplift approvals achieved due to increased pullout values; contact Carlisle for specifics.
Specifications Table:
| Specification | Details |
|---|---|
| Brand | Carlisle |
| Sell unit | 1 box (250 or 500 fasteners depending on length) |
| Product line | HP-XTRA Fasteners |
| Available colors | Mill |
| Available sizes | 2 in., 7 in., 9 in., 10 in., 12 in. (#21); 7-12 in. boxes of 250, 2 in. boxes of 500 |
| Material | Steel |
| Thread | #21 steel-threaded, 13 threads per inch buttress thread |
| Point | Mini drill point |
| Head | Oversized truss head, #3 Phillips drive |
| Coating | Black epoxy electro-deposition |
| Pullout value | Typical 900 lb in 22-gauge Grade E steel deck |
| Deck compatibility | 22-gauge (0.76 mm) steel decks |
| System compatibility | Used with PIRANHA XTRA Fastening Plates to secure mechanically fastened Sure-Weld roofing systems |
| Included | One #3 Phillips screwdriver bit per bucket |
| Approvals | Enhanced Factory Mutual uplift approvals; coating surpasses FM 4470 corrosion test (less than 15% red rust after 15 Kesternich cycles); contact Carlisle for FM approval specifics |
Coverage & How Much You Need:
Fastener count depends on deck pattern and specified fastener density; plan quantity from the roof assembly's fastening layout. Boxes contain 250 fasteners (7 in. through 12 in.) or 500 fasteners (2 in.).
Fit and Compatibility:
Designed for use with Carlisle PIRANHA XTRA Fastening Plates to secure mechanically fastened Sure-Weld roofing systems to 22-gauge (0.76 mm) steel decks. Plates are sold separately.
Frequently Asked Questions (FAQ):
Q: What sizes and box counts are available?
A: The line includes 2 in. (500 per box) and 7, 9, 10, and 12 in. (250 per box) #21 fasteners in mill finish.
Q: What decks do these fasten to?
A: They are designed for 22-gauge (0.76 mm) steel decks, where typical pullout values of 900 pounds are achieved in Grade E deck.
Q: Are fastening plates included?
A: No. They are used with PIRANHA XTRA Fastening Plates, which are sold separately.
Q: How corrosion resistant are they?
A: The black epoxy electro-deposition coating surpasses the FM 4470 corrosion test of less than 15% red rust after 15 cycles in the Kesternich cabinet.
Q: Is a driver bit included?
A: Yes. One #3 Phillips screwdriver bit is included in each bucket.
Expert Verdict — Reviewed by the SuperArbor Pro Desk
Pick the fastener length to suit insulation build-up plus deck engagement over 22-gauge steel, using the 2 in. for thin builds and longer lengths for thicker assemblies. These fasteners earn their keep in high-wind, FM-specified designs where the 900 lb typical pullout and back-out resistance matter. Always pair them with PIRANHA XTRA plates and drive with the included #3 Phillips bit at a consistent depth.
Steel fasteners have sharp drill points; wear gloves and eye protection, and use calibrated screwguns to avoid overdriving through the deck.
Order Carlisle HP-XTRA Fasteners today for maximum pullout in 22-gauge steel decks.
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