ALEXANDRIA, Va., Feb. 5 -- United States Patent no. 12,214,239, issued on Feb. 4, was assigned to Yongkang Zuojian Industry and Trade Co. Ltd. (Yongkang, China).
"Dumbbell, barbell, and kettlebell" was invented by Zhaohong Yu (Yongkang, China) and Xiaoqing Xu (Hangzhou, China).
According to the abstract* released by the U.S. Patent & Trademark Office: "The present disclosure provides a simple dumbbell including a dumbbell rod, an adjustment component, and a dumbbell piece. Two semicircular telescopic rods are provided in the dumbbell rod, a square groove is provided in a middle of the two semicircular telescopic rods. A square rod is provided on the square groove, a fix hole is respectively provided at two ends of the square rod. A limit ...