M3 Stainless Steel Flat Washer A2 DIN125 50-Pack

M3 Stainless Steel Flat Washer — A2 DIN125, 50-Pack

M3 A2 stainless steel DIN125 flat washers distribute the clamping load of M3 screws and bolts over a larger surface area, preventing pull-through in soft materials, protecting surface finishes, and providing a smooth bearing surface for nut tightening. Essential for PCB mounting, 3D printer assembly, and electronics enclosure fastening where direct screw head contact would damage the substrate.

Key Specifications

Why Choose M3 A2 Stainless Flat Washers?

• Load distribution — 7mm OD spreads clamping force over a larger area; prevents screw head pull-through in PCB laminates, plastic panels, and thin sheet metal
• Surface protection — smooth washer face protects anodised aluminium, painted surfaces, and PCB silkscreen from screw head damage during tightening
• A2 stainless steel — corrosion-resistant; will not rust or stain electronics enclosures and outdoor equipment
• DIN125 standard — internationally specified; compatible with all M3 screws, bolts, and nuts
• 50-pack quantity — practical workshop stock for prototyping and production

Typical Applications

• PCB mounting — under screw head and under nut to protect PCB surface
• 3D printer frame and panel assembly (Voron, Bambu Lab, Prusa builds)
• Electronics enclosure panel mounting — protecting anodised aluminium surface
• Raspberry Pi and SBC case assembly
• Robotics chassis and bracket mounting — load distribution on thin sheet metal
• Nylon and plastic panel mounting — preventing pull-through

Compatible With

• All M3 machine screws, cap screws, and bolts
• M3 hex nuts, nyloc nuts, and flange lock nuts
• M3 split lock washers (used together for vibration resistance)
• PCB mounting holes: standard 3.2mm clearance drill

Package Contents

• 50× M3 A2 stainless steel DIN125 flat washers

Frequently Asked Questions

Q: Should I use a flat washer under the screw head, under the nut, or both?

A: For maximum protection, use a flat washer under both the screw head and the nut. Under the screw head: protects the surface from damage during tightening. Under the nut: provides a smooth bearing surface and distributes load. For PCB mounting, always use a washer under the screw head to protect the PCB surface.

Q: What is the difference between a flat washer and a split lock washer?

A: A flat washer (DIN125) distributes load and protects surfaces. A split lock washer (DIN127) provides spring tension that resists vibration loosening. For vibration-prone applications, use both: flat washer first (against the surface), then split lock washer, then nut.

Q: What is the outer diameter of an M3 flat washer?

A: M3 DIN125 flat washer OD is 7mm, ID is 3.2mm, thickness is 0.5mm. These are standard dimensions compatible with all M3 screws and bolts.