Redshift ShockStop PRO Suspension Seatpost 27.2 mm - 350 mm
Amazon.com : REDSHIFT ShockStop Suspension Seatpost for Bicycles, Shock-Absorber Bike Seat Post for Road, Gravel, Hybrid, and E-Bikes, 27.2mm x 280mm : Sports & Outdoors
Redshift ShockStop Pro suspension seatpost review: An awkward middle ground - Velo
REDSHIFT Assembly & Review: The Shockstop Suspension Seatpost - YouTube
Review: Redshift ShockStop may just change your mind about suspension seatposts - Bikerumor