... pound size material:cast iron and outside is neoprene. Neoprene coated kettlebell :spec:KG or pound sizematerial:cast iron and outside ... is neoprene.color:can be choosed as your demand.commodityNeoprene coated kettlebellmaterialironspecification4kg,8kg,12kg,16kg,20kg,24kg,28kg,32kg,36kg,40kg ...