31.9 size Think it’s 150mm drop Working order
Trans X Dropper Post J20L4 150mm x 34.9mm Adjuster Seat Mount 2 Bolt Clamp
Tranz-X Dropper Post 31.6mm x 450mm, 150mm Travel, Black, Mountain Bike
Brand x Kids Dropper Post 27.2mm Post 70mm Travel
BRAND-X ASCEND V2 1x Dropper Post Remote Lever - Shimano I-Spec II Mount
