M3 Fasteners | McMaster-Carr

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2,691 Products

Fastening and Joining

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

Hex Head Screws

Hex Head Screws

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

Set Screws

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

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

Captive Panel Screws

Captive Panel Screws

Secure panels and enclosures while still having access to them

Tapping Screws

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

Studs

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

Threaded Inserts

Threaded Inserts

Create new threads or repair stripped threads

Press-Fit Nuts

Push into drilled or punched holes to add threads to thin panels

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

Hex Nuts

Handle most general fastening needs

Locknuts

Hold fasteners in place to prevent loosening from vibration

Cap Nuts

Cover and protect threads while adding a finished look; also known as acorn nuts

Slotted Round Nuts

Slotted Round Nuts

Fasten with a screwdriver in tight spots where there's no room for a wrench

Flange Nuts

The flange distributes pressure, so you don't need a washer

Sealing Nuts

Prevent leaks and block out contaminants with a rubber seal

Easy to tighten and loosen by hand for making frequent adjustments

Coupling Nuts

Connect and extend threaded rods

Socket Nuts

Install in recessed holes and tight spots where a wrench won’t fit; also known as Allen nuts

Square Nuts

Flat sides won’t spin in channels and square holes

Standoffs

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

Threaded Rods

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

Single-End Studs

Single-End Studs

Use the unthreaded end as a pivot point, hinge, shaft, or locator pin

Thread Adapters

Thread Adapters

Join threads of a different type, size, and gender

Dowel Pins

Align parts before assembly or use as a pivot, shaft, or hinge to join moving components

Push Nut Installation Tools

Push Nut Installation Tools

Press nuts and retaining rings onto threaded fasteners and shafts

Rivet Nut Tools

Rivet Nut Tools

Install rivet nuts

Building and Machinery Hardware

T-Slotted Framing and Fittings

T-Slotted Framing and Fittings

The most versatile system, attach fittings along the continuous slots to build virtually anything

Cam Handles

For fast clamping, push down on the handle to draw two parts together

Power Transmission

Connecting Rods

Connecting Rods

Use with rod ends and swivel joints to link components in push/pull assemblies

Lead Screws and Nuts

Lead Screws and Nuts

Components travel along a screw with broad, square threads to clamp and lift heavy loads

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