These are about 70% larger than the small set. These cast iron bolsters take a lot of the work and all of the welding out of making a cart for your engine. One pair of stationary and a pivoting bolster with axle mounting hardware designed to work with axles 1 5/16″ to 2″ in diameter recommended for use on engines 4hp and up. A lot of you have bought wheels in the past with the idea of actually using them one day, well dig them out and dust them off (or leave the dust on) now is your chance to put them back to work even if they take different size axles, due to the design you can run any combination of 1 5/16″ to 2″diameter axles between the front and rear. Bolsters are 5 1/2″ tall and the width spacing between the mounting holes on the pivoting bolster base is 9 ¾”. Finished height of cart will vary depending on the diameter of the wheels used. Cast iron will give an antique look many prefer over fabricated strap steel and help your engine really stand out at the next show. Can of root beer for size comparison, not included. Photo of finished cart is for reference only, wheels engine etc are not included.