QUALITY DOUBLE-ENDERS. DOUBLE THE FUN. Whether you’re out tackling a rushing stream or a glass-calm lake, a first-timer or professional outfitter, a Grumman versatile double-ender is the right choice. Its wide beam and low profile give stability and reduced wind resistance. The double-ender is available in various standard weight models, from 13 to 18 feet. A 17 ft. 5 rib version is built specifically for camps and outfitters. Choose standard or shallow draft keels built to meet the needs of flatwater canoers or whitewater challengers.