In the existing Alpha (A-mount) DSLR system, this dimension was 40mm. For the Sony E-mount ... because it means the pair can also share lens caps, saving fumbling in your pocket for the second ...

Note that there's no standard-definition video connectivity, though. The Sony Alpha DSLR-A290 is priced at $499.99 with an 18-55mm kit lens, and ships in the USA from July 2010.