Whole transparent, smooth surface,operate flexible Size: S, M, L 1.Types: middle screw type.2.Sizes: Large,Medium,Small.( In compliance with international standrad )3.Material: polystyrene ( short for :PS )4.Sterilization: Our factory has sterilization chamber . By EO gas. nontoxic5.Service : OEM service is available . usage(1).lateral screw type:often used in Europe,Southeast Asia and some ...