Safe And Reliable Material: Made of stainless steel and rubber, durable in use, non-slip and avoid scratching your portafilter or your hand. Rubber bar and Stainless Steel body are able to reduce the noise when used. Strong Stability: The knock box features a non-slip rubber pad on the bottom to stabilize the knock box and reduce noise, prevent sliding, and won't scratch kitchen countertops. Easy To Maintain: Knock boxes are essential espresso accessories, and they require minimal maintenance. Yes, you do need to wash them every once in a while. But, they are very easy to clean, so you don't need to give it much effort. Great Size: The coffee waste bin only is perfect for storing underneath most espresso machines. The espresso machine knock box capacity is large enough that you don't have to empty it too often Widely Use: Bar Coffee Dump Bin is Suitable for coffee shops, milk tea shops, bars, and wonderful standby tools. Widely used at home, cafe shops, canteen, restaurants, bars, and more. Material: stainless steel + rubber Size: 11*11cm/4.33*4.33inch Color:sliver packing list Coffee grounds bucket * 1