Individual 4-ft. single-tube section locks together quickly with the four-piece, 16-ft. Ladder Sticks (sold separately) to get you even higher in your tree. It lets you build a custom-height, lightweight, rock-solid and easy-to-use ladder. Pivoting V-brackets adjust to match tree contours. Fits 4" to 22" tree diameters. Available: 4-ft. extension.