Stellar Intrepid 18′ Sea Kayak (SI18) The Stellar Intrepid 18′ (SI18) Sea Kayak, a very capable and more traditional hull design. Hard chines, a defined keel and a retractable skeg provide excellent handling in the Rock-Gardens or longer adventures. With 3 sealed storage compartments, a small day hatch in front of the cockpit and deck rigging, the SI18 provides plenty of storage options and accessibility. A molded seat pad and thigh brace provide comfort and stability when it gets rough. Length:17′ 11\