Up for sale is HARDDRIVE 2008-2017 FXDF Dyna Fat Bob Harley Davidson DYNA MONOTUBE SHOCK 13" HVY R0800146-2. The vendor part number is R0800146-2. Please read the title to know what is for sale. Catalog Description� Speed Adaptive Valving (SAV) Internal Floating Piston (IFP) stabilizes damping performance One-Piece damping body construction forged from A7075 aluminum Easy set up spring preload cap, no special tool needed . HardDrive Bazooka rear shocks with RacingBros� race proven SAV, �Speed Adaptive Valving�, damping system provides superior ride quality regardless of road conditions!