The ServoCity 4mm ID Aluminum Spacer (8mm OD, 30mm Length) - 4 Pack is a lightweight structural component designed to fit over an M4 screw, providing necessary spacing between parts. Its 8mm outer diameter offers enhanced stability compared to smaller alternatives, making it ideal for applications requiring a larger footprint. Constructed from aluminum with a clear anodized finish, this spacer combines durability with a sleek appearance.