PP tube/HDPE Closure. Medical grade resin conforming to USP class VI. Leak proof with easy 3/4 turn and final 1/4 turn for perfect seal. Packed in resealable bags. Highly visible graduations and labeling area. Star foot design. Certified DNAse, RNAse and pyrogen-free. Withstand temperatures from -196 ºC up to 40 ºC. With exterior screw cap. Sterilized by gamma irradiation. Sterilization certificate included (to be downloaded free of charge here)