McMaster 2481T32 Rubber Solid-Tread Flat-Free Wheel on Aluminum Core, Center-Mount Hub with Roller Bearing, 12" Diameter × 2-3/4" Wide 38UK60 Drive 6 pt Deep Sockets:

Drive 6 pt Deep Sockets: SAE 5/8

They are often used as hinge pins and as fasteners for springs and power transmission components

Steam Pressure 2500 psi@350 Degrees F Specific Pipe Fitting Shape Hex Reducing Bushing Max

UN Rating 1H2/X100/S

McMaster 2481T32 Rubber Solid-Tread Flat-Free Wheel on Aluminum Core, Center-Mount Hub with Roller Bearing, 12" Diameter × 2-3/4" Wide 38UK60 Drive 6 pt Deep Sockets:Hub Mount Location Center Bearing Type Roller Wheel Tread Material Rubber Tread Style Solid Hub Material Aluminum Diameter 12" Width 2 3 4" Hub Length 3 1 4" Weight Capacity per Wheel 800 lb. Tread Pattern Straight Line Hardness Rating Soft Hardness Durometer 60A Nonmarking Wheels No Minimum Temperature 40 F Maximum Temperature 120 F For Surface Type Asphalt, Bar Grating, Brick, Concrete, Hardwood, Linoleum, Steel, Tile Wheel Color Black Wheel Type