The 12-Port Drying Chamber with PTFE is made of type 304 stainless steel with a corrosion-resistant PTFE-coated interior. Includes 12 neoprene valves with plastic knobs that accommodate both 1/2" and 3/4" adapters for connection of flasks, a 1/2" thick arcylic lid with neoprene gasket, and one latching pin. It is compatible with FreeZone 1, 2.5, 4.5, 6, 8, 12 or 18 Liter Freeze Dryers.