Double Locking Black Plastic Two Wheel Swivel Casters M12X1.75 Threading Bolt 4 Pack You you depress the foot activated lock it locks both the ability to roll as well as the ability to swivel. 2-7/8" Diameter Wheels M12-1.75 swivel bolts 2-3/16" Wide 3-5/16" tall without adding in the bolt length (minimum floor lift) 4-1/2" Tall overall length with the bolt included in measurement.