This black plastic shelf slides onto the ledge of your stand, instantly converting it to a double lip orchestral music stand. This shelf that is 5 inches long,2.7 inch depth, 3 inch high. This is a very convenient storage for tuner, metronome and pens. 2 easy options, without a tray and with a tray. it comes with an anti slip tape. tray case: 5 inch, 1.5 inch depth 0.8 inch high, total weight 2 oz