SRP is a replacement plug for Santa Barbara Instruments Group standard desiccant plug for ST-7, 8, 9, 10, 1001, 2000 (E, XE, XME) series cameras. These are a great update for your camera. It completely cured my frost issues and is a lot easier than baking. I bought an extra when I thought I was adding another camera. That deal fell through - no reason to keep an extra SRP. This has never been unwrapped.