This is a 4-layer stack case for Raspberry Pi family. It is compatible with all current Raspberry Pi's including 3 B, 2 B, B+, A+, B and A. You can build more layers on this 4-layer case by purchasing our Stackable Kits. (http://www.amazon.com/gp/product/B00MRLM9QS/). This case is 122.4mm (4.8") high (without the rubber feet), 103.4mm (4.1") long, and 74.4mm (2.9") wide. Each internal layer is 27.8mm (1.1") high. Contact us if you need more space for any layer. You need to peel off the protective paper off before using.