All-plastic closures for aseptic liquid transfer of media, biological reagents and chemicals to and from Nalgene® carboys. Can be used with any large Nalgene™carboys or bottles that accept 53mm (53B) or 83mm (83B) closures. Choice of 1/2"(13mm) or 1/4"inch (6mm) I.D. tubing on 83B closure. Can be used with Nalgene™carboys with a properly set up peristaltic pump. Autoclavable.