ALEXANDRIA, Va., Feb. 26 -- United States Patent no. 12,233,299, issued on Feb. 25.
"Weight training sled with enhanced load effect" was invented by Ya-Chi Chen (New Taipei, Taiwan).
According to the abstract* released by the U.S. Patent & Trademark Office: "A weight training sled with enhanced load effect is disclosed. The main frame has a first end and a second end remote from each other. Two first wheels, in a rotatable state, disposed at either side of the first end. A second wheel, in a rotatable state, disposed at the second end. The damping structure, disposed on the main frame and connected to the second wheel. An operating handle, erected at the first end of the main frame. An auxiliary push frame, erected at the second end of th...