Amazon.com: Saipe 31.8mm Bike Seat Post Clamp Seatpost Collar Aluminium Alloy SeatPost Clamp for 27.2 Bicycle seat Post MTB Bike Road Bike Casual Bike : Sports & Outdoors
Promax 335QX Quick Release Seatpost Clamp - 31.8mm - The Bike Shop
Aluminium Alloy Bike Seatpost Clamp,Seat Post Tube Clip 34.9/31.8mm Holder - AliExpress
Dimension 31.8mm Heavy Duty Seatpost Clamp Black - Philbrick's Ski, Board, & Bike
Amazon.com : Bike Bicycle Quick Release SeatPost Clamp 34.9mm 31.8mm MTB Bike Road Bike Casual Bike Seatpost Clamp (34.9B) : Sports & Outdoors