Off-road high performance rear shock for the Kawasaki KLX230 family.  30% increase in spring rate with adjustable preload, rebound, and gas pressure.  A huge performance increase over the stock rear shock.  The early S models as well as the Sherpa had a shorter 445mm (17.5") rear shock, whereas the later models and the  DF, R, and RS have a longer 460mm (18.12") shock length.  Please measure twice and order once to ensure that you get the correct one for your bike.  
 
Installation note:  This assembly is physically larger than OEM and hits the corner of the battery box.  This requires the battery box to be removed and trimmed for proper installation.  Pictures in the ad show the portion of the box that needs to be trimmed.  Increase the height of the hole in the left rear bottom corner of the box by about 1".