To add detail to the already excellent answers, it's a truvativ Elita crankset, which uses a Truvativ/Sram GXP external bottom bracket. SRAM own Truvativ and their cranksets all use the same BBs. It has the same dents round the outside (16 I think) as Shimano, so uses the same tool as Hollowtech II to remove and install. The BB has a different, smaller I think, axel size, so the BBs are not interchangeable with Shimano Hollowtech II BBs.
The exception is that Hope make shims/adapters so their shimano-sized BB can be used with Truvativ/Sram Cranksets. It may be possible to use these adapters with other makes of BB too, so as to convert a shimano sized BB to truvativ/sram GXP size.