Diecast Aluminum Frame. Stamped Aluminum Right Sideplate. Aluminum Braced Graphite Non-Handle Side Plate. Aluminum Spool. Rod Clamp. Manual Clutch (excluding 500LC and 600LC which are Auto-Return). A-RB (Anti-Rust Bearings). Super Stopper is a one-way roller bearing that eliminates backplay for solid hooksets. Assist Stopper is a back-up anti-reverse system that reduces the stress placed on the one-way roller bearing to increase durability. Dartainium Drag material provides a wide range of drag settings and the smoothest Shimano drag performance ever. Oversized Cast Control Knob comfortable and easy to use. Clicker. Septon handle grip material. Oversized Clicker Button easy to turn on and off. Counter Balanced Handle (excluding models 700 and 800). Adjustable Handle Shank (only models 700 and 800). Optional Double Paddle Handle allows the angler to purchase, as an accesory, a double paddle handle for certain applications (Available on 500, 500LC, 600 and 600LC only). Non-Disengaging Levelwind System Allows the levelwind to track back and forth during the cast which reduces drastic line angles that cause unwanted friction and backlashes on wide-spool reels. Palmable Linecounter with Maintenance Port (only 500LC and 600LC). Crossbar Forward Design. Metal Series Metal frames.