Teflon® PTFE crucibles are non-contaminating and completely resistant and inert to chemical attack. Unbreakable, easy to clean, light weight and microwavable. Moulded in pure, FDA approved, PTFE with machined bottoms for excellent heat transfer with a moulded-in pour spout. Autoclavable. Service Temperature of -200 to 250°C. They are non-wettable, unbreakable, lightweight, and heat resistant. Easy to clean, these beakers have a broad wide top with a lid.