Looks like a fairly typical suspension seatpost. They're generally pretty terrible and are a dead weight, I'd replace with a standard seatpost unless he's particularly attached to it.
Thanks both....should of guessed ! I'm not that we'll up on mountain bikes.
I think of them as a (poor) halfway house between a normal post and a dropper.
Next question decent seatpost anyone ? Link to one maybe,only son so as little cost as possible 😁
Cheers Andy just need to work out the size .
Cheers Andy just need to work out the size .