This is an SRM powermeter (172.5mm crank arm length) that I purchased around the beginning of 2009. Earlier this year, I sent it to SRM for a “refurb”- new batteries in the PCV and SRM along with a thorough cleaning of the internals of the powermeter. It works beautifully, but I’ve since gone wireless. Price doesn’t include a GXP bottom bracket, but if you’re interested, I could work out a deal on a new one for you.