This 3T is a 4 bolt face and is narrow enough
but agree on the Thomson stuff -- anything they make is first rate -- using Thomson for my seatpost nub (just a regular cutdown road post inserted in the seat mast ) -- it doesn't slip
And the reason for the extended seat mast is for the exact reason @
carleton stated -- slipping seatposts suck --- and if mine does , it will only slip an inch or so and I can ride through that
Sadly -- had a moment of "adulthood" and the car is long gone now
