Heavy steel construction; solid rubber base keeps the box in one place; requires no installation; easy to clean out; sturdy rubber padded knock bar; great value even at the list price of $19.95; and looks like it's built to last.
Negative Product Points
Can only hold about six pucks; you have to shake to box around to get more than 3 pucks to fit; Coffee can splash through keyhole shaped slots used to hold the removable knock bar; and Shiny steel box is hard to keep shiny and does not match the brushed steel of Silvia, Rocky and kitchen appliances.
I ordered this knock box from Espresso Parts NW and really did not expect to get such a well made product for only $15.95 (on sale, regular price was $19.95). The box is made of heavy gauge steel with a solidly welded bottom that looks like it will never leak. The rubber base is also very heavy and fits snugly to the bottom of the steel box. The base does a great job of keeping the box stable whild you are knocking out a puck. The knock bar is heavy steel with a thick ribber pad so there is no fear of damaging your portafilter which is most likely made of soft brass. The box itself is has an aesthetically pleasing shape which tapers gracefully outward and upward from the base. Sort of like a section of an obelisks turned upside down. Imagine a section of the Washiington Monument turned upside down and placed in a rubber base! The front features a graceful cutout that makes knocking out a puck easy. The six puck capacity can be a problem if you are making a lot of coffee but for serving one or two people it is not a problem.
Purchased from Espresso Parts NW, the only vendor that seems to have this particular model. Order filled, billed and shipped promptly and properly.