This is a package of DUBRO wheel collars generally used to secure the wheels on the axles on an airplane but can be used for other applications as well. FEATURES: Plated brass Uses a set screw to lock collar to the axle INCLUDES: Twelve wheel collars Twelve 4-40 set screws One .050" allen wrench SPECS: inside diameter - 1/16" outside diameter - 7/32" thickness - 3/16" btm 06/11/94BOX DIMENSIONS: 3.00" W. X .25" H. X 3.25" L.BOX WEIGHT: .03 LBS.