Motorcycle Solo Seat Shock Spring with Mounting Hardware Available in 4", 5" and 6" Lengths - For Custom Motorcycle Applications - SOLD INDIVIDUALLY - 300 Pounds/Inch Spring Rate (BPD-2792X)
Amazon.com : BESNIN Bike seat Shock Absorber Hock Absorbent Saddle Spring Seat Shock Absorber Universal Bike Saddles Shock Absorber for City Bikes AL6061 Withstand 120KG MAX : Sports & Outdoors