The Hidden Hitch 5th Wheel Hitch Signature Series comes in 2 different styles: 18K Signature Series; 24K Signature Series. The Signature Series also comes with a forged single jaw that increases the kingpin/jaw contact, a self-latching jaw, and a king pin indicator. The signature series has a wider footprint for increased stability, a stamped rounded head and a wider 9" (vs. 6") kingpin funnel area on the head. The 18K Signature series has all the 16K features plus an 18,000 lb. gross/ 4,500 pin weight capacity. The 18K Signature Series has an improved 4-way head pivot, a 4 degree side to side head pivot for better control and an longer handle. The 24K Signature Series comes with all the features of the 18K and 18k Signature Series plus a 24,000 lb gross/6,000 pin weight capacity, a reinforced head, a heavier forged jaw, and a higher capacity head support structure. The Signature Series 5th wheel hitch needs the Power Puck mounting system. Which is sold seperately. The Signature Series 5th Wheel Hitch also has an optional Slider Rail Kit. The Hidden Hitch Slider Rail Kit fits only the 18K Signature Series 5th Wheel Hitch. The Slider Rail Kit has 10” of travel, a round rail design that allows for a smoother operation. The Slider Rail Kit will even operate when your vehicle is not in a straight line.