Orbital" 5/16 Size" 6 The 3M Random Orbital Sanders are pneumatically powered, light weight and have the lowest profile available on the market. The sanders are available in 3 orbit styles and are available in Non-Vacuum, Central Vacuum, and Self Generating Vacuum models. The sander, along with 3M's high quality abrasives, produce superior finishes with long abrasive life and good cut rates.