My SB is 32" x 49" and 12" deep. However, if you have the privacy curtain, more than half of the depth is used up by the framing. I removed the original frame and installed SS slide hinges from Amazon, with aluminum square tubes - I currently store my fishing tackle, a fold-up porta potty and supplies, plus about 8 life jackets. My Benny is stored 6 hours from home - so I created this to help me with the original storage plan.