Aluminum Spacer 3/8" OD x 1/4" ID x Many Lengths Round by Metal Spacers Online (1/2" Length, 10)
Brand: MetalSpacersOnline.com

All aluminum spacers have a tumbled finish

Outside diameter: 3/8"/9.52mm
Inside diameter: 1/4"/6.52mm (fits 1/4" or M6 bolts)
Length: Varies-Choose Length
Shape: Round
Material Type: T-6061 Aluminum