Engineered with a solid cast iron core encased in premium PVC material, these weights resist rust, cracking, and chipping while eliminating unpleasant rubber odors. ????️ COMPREHENSIVE WEIGHT SELECTION: Available in six weight options from 5 lbs to 50 lbs, this dumbbell set includes a 100 lb starter collection with pairs of 20 lb and 30 lb hex weights for versatile muscle training.