Material: plastic (polyamide 12). Autoclavable: yes. Note on grinding tolerances for ground glass joint 29 Max. outer Ø at the narrowest point of the conical ground joint: 31.4 mm (larger Ø are too wide for the holder and cannot be held) Min. outer Ø at the widest point of the conical ground joint: 32.8 mm (smaller Ø are too narrow for the holder and would fall out) Holder for glassware with ground glass joint 29, with locking device for SmartRack ® The module corresponds to the module holder for glassware with ground glass joint 29, but is also equipped with a rotating locking ring that provides additional protection for glassware with ground glass joint 29 against falling out. Delivery without glassware.