Nice carbon seatpost, 350mm length, 31.6 diameter. This is virtually new but on its one ride, the saddle was constantly slipping. Turns out the saddle clamp bolt seems to be faulty (or - ahem - possibly stripped by yours truly on installation).
I now have a replacement post (same model, no issues this time!) so this one is surplus to requirements, and I've also been offered 50% off a new saddle clamp mechanism from 3T (this) which comes out at around £18 including postage.
I'd rather not bin it, so if anyone is interested in taking this off my hands, I can send you the post as it is for the cost of postage, or I can order the new mechanism and send you both parts - you just cover the costs, again.