... ) Material: polyether TPU 0.7mm or PVC plastic roller ball Specifications for zorb balls,grass walking balls,water ... much fun for people;(5) Competitive price. Plastic roller Size: The wheel outside diameter is 2.4m, ... is very durable. No.3: Safe The old roller ball floats on water based on the air chamber ... have the feeling with the water. The new roller only has a single material, players will have ...