Amazon.com : Rmiott Bike Suspension Seat Post Shock Absorber 27.2mm 400mm Length 50mm Travel Aluminum Adjustable : Sports & Outdoors
Nitto S67 Seatpost - 31.6 x 460mm
GEWAGE Suspension Seatpost for Bicycles - 27.2/30.9/31.6 X 400mm Shock Absorbing Bike Seatposts - Lightweight Aluminum Alloy Seat Post for MTB Road Bike BMX eBike - Walmart.com
Upanbike Bike Seat Post φ 25.4/27.2/28.6/30.9/31.6mm, Length 13.8inch (350mm) Aluminium Alloy Bicycle Seatpost (φ 31.6mm) - Walmart.com
PNW Rainier Gen 3 Seatpost 31.6 dia 170mm - BikeCo.com