Used for about 8 months. Compatible with both microwave and liquid sterilization. Also usable as a bottle case. *Includes the instruction manual and a lid to submerge nipples and other parts. Used several times a day for 8 months, so there is a sense of use. Please understand that this is a used item before purchasing. By the way, I never used adult dish sponges when washing. I washed everything with a baby sponge and natural soap. -Excerpt from the product description- 1. Chemical sterilization (disinfection) 2. Steam sterilization in the microwave 3. Storage case A "3-in-1" sterilization case that can be used for chemical sterilization (disinfection), microwave sterilization, and bottle storage. The draining basket allows you to easily remove the bottles without touching them directly, reducing the time it takes to sterilize them. ●Material: Polypropylene (case, draining basket, lid, drop-in lid, measuring cup) ●Heat resistance: 140℃ Cold resistance: -30℃