4-40 Bolts | McMaster-Carr

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2,686 Products

Fastening and Joining

Hex Head Screws

Hex Head Screws

Used with nuts to create a stronger joint than flat and rounded screws

Socket Head Screws

Socket Head Screws

With a deeper drive than flat and rounded head screws, these withstand more torque for a tighter hold

Rounded Head Screws

Rounded Head Screws

Sit just above the surface for a low-profile finish and hold tighter than flat head screws

Flat Head Screws

Flat Head Screws

Fit in countersunk holes for a flush finish

Shoulder Screws

Shoulder Screws

Rotate parts around the cylinder under the head to guide and align them during installation

Tighten and loosen by hand without the need for tools

Set Screws

Exert pressure at the tip to hold parts in place, unlike screws that hold material together with threads

Tapping Screws

Fasten a range of materials together without needing to tap the hole first

Captive Panel Screws

Captive Panel Screws

Secure panels and enclosures while still having access to them

Jack Screws

Secure computer cables and panels

Studs

Press, weld, or screw in place to add a threaded fastening point

Standoff Caps

Create a finished look on standoffs and protect them from dirt and debris

Standoffs

Threaded to separate or connect parts as well as position components in assemblies

Thread Adapters

Thread Adapters

Join threads of a different type, size, and gender

Threaded Rods

Anchor, connect, or hang components in a wide variety of applications

Rivet Nuts

Add threads to thin panels with access from only one side; also known as blind inserts

Weld Nuts

Weld to metal surfaces to add permanent threads

Stud Welders

Join studs and pins to metal, leaving no marks on the back of the material

Fabricating and Machining

Clamps

Hold workpieces securely in place

The quick brown fox jumped over the lazy dog. Pedestal (35" Ht. x 4" Wd. x 4" Dp.)