These are awesome, high quality, custom made aluminum spacers. They are great at making sturdy standoffs/spacings for your projects., These Metric
M16 x 25mm O/D x 30mm Length Spacers - 303 Stainless Steel
Aluminum Spacers - 10 Packs
ALUMINUM 7075 CONE SPACERS BLACK ANODIZED – QS Components, Inc.
Aluminum Metric Spacer, M3 Screw, 8mm OD x 3.2mm ID x 5 mm Length
Lyn-Tron, Aluminum, Metric, M3 Screw Size, 8 millimeters OD, 3.2
Bearing Spacer for Metric GM
Spacers by Metric Hole
Aluminium threaded spacer diameter 30mm length 100mm M10
Lead CNC V3 Mechanical Kit – 1500 x 1500 - SILVER - Maker Store USA
Everbilt #5/16 x 1/4 in. Chrome Steel Spacer 800284 - The Home Depot