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    30 Products
    About Tapping Screws
    industrial info icon

    Compare drilling, pointed, thread-forming, and thread-cutting tips to find the best choice for your material.

    Stainless Steel Phillips Rounded Head Thread-Cutting Screws for Plastic

    Image of Product. Front orientation. Tapping Screws. Stainless Steel Phillips Rounded Head Thread-Cutting Screws for Plastic.
    Image of Specification. Round Shank Cross Section. Front orientation. Round. For Plastic.

    Round

    Shank

    Cross

    Section

    Often used in glass-filled nylon and other tough thermoplastics, these screws create threads where thread-forming screws can’t. They cut away material as they drive to fasten without deforming the hole and have coarse threads for a sure grip. The Phillips drive handles enough torque to keep drivers from slipping and the rounded head creates a finished look. Also known as Type BT and Type 25 screws.
    Length is measured from under the head.
    410 Stainless Steel—Tougher and more wear resistant than other stainless steel screws but less corrosion resistant.
    Round—The sharply angled threads drive into plastic with less force and a lower risk of cracking than other tapping screws. The base of the threads is recessed to bite deep into material and hold tight. You can reuse these screws a few times without stripping the threads. They're comparable to PT screws.
    Head
    Lg.
    Dia.
    Ht.
    Tapping
    Screw Type
    Drive
    Size
    Approx. Threads
    per In.
    Drill Bit
    Size
    Shank Cross
    Section
    Pkg.
    Qty.
    Pkg.
    410 Stainless Steel
     
    No. 2 Screw Size
    1/4"0.167"0.062"25/BTNo. 13249 Ga.
    Round10000000000000000
    5/16"0.167"0.062"25/BTNo. 13249 Ga.
    Round10000000000000000
    3/8"0.167"0.062"25/BTNo. 13249 Ga.
    Round10000000000000000
    1/2"0.167"0.062"25/BTNo. 13249 Ga.
    Round10000000000000000
     
    No. 4 Screw Size
    1/4"0.219"0.08"25/BTNo. 12441 Ga.
    Round1000000000000000
    5/16"0.219"0.08"25/BTNo. 12441 Ga.
    Round1000000000000000
    3/8"0.219"0.08"25/BTNo. 12441 Ga.
    Round1000000000000000
    1/2"0.219"0.08"25/BTNo. 12441 Ga.
    Round1000000000000000
    3/4"0.219"0.08"25/BTNo. 12441 Ga.
    Round1000000000000000
     
    No. 6 Screw Size
    1/4"0.27"0.097"25/BTNo. 22031 Ga.
    Round1000000000000000
    5/16"0.27"0.097"25/BTNo. 22031 Ga.
    Round1000000000000000
    3/8"0.27"0.097"25/BTNo. 22031 Ga.
    Round1000000000000000
    1/2"0.27"0.097"25/BTNo. 22031 Ga.
    Round1000000000000000
    5/8"0.27"0.097"25/BTNo. 22031 Ga.
    Round10000000000000000
    3/4"0.27"0.097"25/BTNo. 22031 Ga.
    Round10000000000000000
    1"0.27"0.097"25/BTNo. 22031 Ga.
    Round10000000000000000
     
    No. 8 Screw Size
    3/8"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
    1/2"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
    5/8"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
    3/4"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
    1"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
    1 1/4"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
    1 1/2"0.322"0.115"25/BTNo. 21826 Ga.
    Round10000000000000000
     
    No. 10 Screw Size
    3/8"0.373"0.133"25/BTNo. 21617 Ga.
    Round10000000000000000
    1/2"0.373"0.133"25/BTNo. 21617 Ga.
    Round10000000000000000
    5/8"0.373"0.133"25/BTNo. 21617 Ga.
    Round10000000000000000
    3/4"0.373"0.133"25/BTNo. 21617 Ga.
    Round10000000000000000
    1"0.373"0.133"25/BTNo. 21617 Ga.
    Round10000000000000000
    1 1/4"0.373"0.133"25/BTNo. 21617 Ga.
    Round5000000000000000
    1 1/2"0.373"0.133"25/BTNo. 21617 Ga.
    Round5000000000000000
     
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