Twilkes
Guru
I got one of these second hand, mainly because it would put my comfy Kona saddle in the same position as my Cannondale's OEM saddle, but I've never seen this way of attaching the rails before.
Rather than clamping above and below, the rails sit in some curved (presumably) plastic moulding and the hex key tightens them from the side.
There seems slightly more flex than the clamp style of seatpost, which might even mean a smoother feeling ride, but are these kind of seatpost just as strong?
It took some getting the rails into the moulding so they are definitely a snug fit, but is the plastic moulding weaker than the usual metal clamps?

Rather than clamping above and below, the rails sit in some curved (presumably) plastic moulding and the hex key tightens them from the side.
There seems slightly more flex than the clamp style of seatpost, which might even mean a smoother feeling ride, but are these kind of seatpost just as strong?
It took some getting the rails into the moulding so they are definitely a snug fit, but is the plastic moulding weaker than the usual metal clamps?
