1、Double Layer Protection: Golf ball has two layers, which is flexible and durable. 2、Hitting Accuracy: Holes on the surface can reduce drag in the air and improve the accuracy of hitting. 3、Hits: Double layer practice ball can withstand more than 800 hits, is easy to play, and can be used for a long time. 4、Ball Parameters: Diameter 42.67mm/1.7in, elasticity about 89%, wind tunnel 332, practice ball suitable for golf enthusiasts training. 5、Quality Material: Ball core is made of synthetic rubber and the outer layer is made of Surlyn resin material, which is durable. Item Type: Double Layer Golf Balls Color: As Picture Shown Hits: More Than 800 Times Weight: Approx.619g/21.8oz Material: Synthetic Rubber + Surlyn Resin 12 x Double Layer Golf Ball