3/8-16 x 3'' self-tapping trailer deck screws, flat head, type F vs 5/16-18 x 3 1/2" self-tapping trailer deck screws, flat head, Type F, T-40 star drive

Overall winner: 3/8-16 x 3'' self-tapping trailer deck screws, flat head, type F

Key Differences

Product A (5/16-18 x 3.5") is positioned in a more affordable price tier and is slightly longer; Product B (3/8-16 x 3") is a thicker diameter intended for heavier fastening needs. Both share the same brand, rating, and similar pros and cons, but A is longer while B offers greater shear strength due to larger diameter

3/8-16 x 3'' self-tapping trailer deck screws, flat head, type F

3/8-16 x 3'' self-tapping trailer deck screws, flat head, type F

Newport Fasteners • ★ 4.2/5 • Mid-Range

Self-tapping screws engineered for wood and metal with a Type F point and star drive. Durable hardened steel with black phosphate and oil coating for rust resistance; suitable for trailer decks and floorboard installations. Customers note easy installation and good value

Pros

  • self-tapping efficiency
  • durable hardened steel
  • rust and corrosion resistance
  • ease of installation

Cons

  • mixed feedback on whether they are self-drilling
  • drill accuracy noted as a concern
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5/16-18 x 3 1/2" self-tapping trailer deck screws, flat head, Type F, T-40 star drive

5/16-18 x 3 1/2" self-tapping trailer deck screws, flat head, Type F, T-40 star drive

Newport Fasteners • ★ 4.2/5 • Mid-Range

Self-tapping screws designed for wood and metal deck installations. Hardened steel with black phosphate and oil coating for corrosion resistance; Type F point for efficient thread cutting. Customer insight notes easy installation and durable performance, with positive feedback on quality and value

Pros

  • self-tapping with Type F point
  • works with wood and metal
  • hardened steel with rust resistance
  • ease of installation

Cons

  • mixed confirmation on self-drilling capability
Check current price on Amazon →

Head-to-Head

CriteriaWinner
Price Newport Fasteners
Durability Tie
Versatility Newport Fasteners
User Reviews Tie