The following sizes are included: 4 Square Budd Wheel Sockets: 1-1/2″ x 13/16″, 35mm x 17mm, 38mm x 20mm, 41mm x 21mm and 1 Deep Socket: 33mm. Chrome molybdenum alloy steel for long life Designed with radius corners, this allows it to grab the sturdy wall of the fastener instead of grabbing the corners