KNOCK KNOCK: Who's there? ABS. ABS who? ABS-olutely the best knock box you'll ever need. The GOMINIMO Coffee Knock Box is made of ABS plastic, which is durable, sturdy, and prevents bacterial growth from inside. You won't have to worry about any nasty surprises when you open the lid. NO SPLASH, NO HASSLE: The knock box has a bayonet deep bay design, which makes the coffee grounds not easy to splash out, and an oblique mouth, which allows for more convenient use. You can dump the grounds without making a mess or hurting your wrist. KNOCK IT OFF: No, seriously, knock it off. The knock bar is made of aluminum and covered in rubber, which has a good buffering performance, reduces the noise, and protects the handle of the espresso machine. The knock bar is also detachable and easy to clean. Just take it off and rinse it under water. NO SLIP, NO TRIP: Don't let your knock box slip away from you. The knock box has an anti-slip design at the bottom, which makes it more stable and secure when knocking out the grounds. You can knock with confidence and avoid any accidents. SIZE MATTERS: The knock box is big enough to hold a decent amount of coffee pucks and the size is perfect for storing underneath most espresso machines. You won't have to empty it too often or struggle to find a place for it.