SHIMANO Sahara 4000 FD Spinning Reel Line Capacity:8/240, 10/200, 12/160, 4 ball bearings. Gear Ratio: 5.7:1S A-RB These bearings have been through the same process as our A-RB bearings, but feature shields on both sides of the bearings that reduce the possibility of salt or sand inhibiting the bearing's rotation. Super Stopper II anti-reverse uses a one-way bearing that eliminates backplay.This provides the angler with instant hooksetting power. In some reels, the Super Stopper II can be turned off to allow backreeling for special techniques and situations.Dyna Balance This feature eliminates wobble during the retrieve by counter balancing the rotor to enhance sensitivity and smoothness. By using computer balancing, an approach similar to car tire balancing, we are able to redistribute the rotor weight to create smooth rotation and eliminate vibrations caused by the reel.