Drawing sails and marlin to the transom with teasers is one of the most effective offshore techniques ever devised. But switch-baiting isn't foolproof, and getting the actual bait to the fish without incurring tangles can be a challenge. Two of my cockpit-savvy friends came up with a switch-baiting tube, which keeps both the pitch bait and the lit-up billfish in the angler's line of sight, unlike with a cooler or bucket. Filled with ice, the tubes keep rigged trolling baits handy and take up very little room. To make a switch-bait tube, cut a 2' length of 6" Schedule 40 PVC pipe. Using PVC adhesive, glue a cap to one end. Drill a 1/2" hole approximately 6" from each end. Drill a 1/16" hole on the opposite side of the tube from each of the 1/2" holes. Saw the handles off two ordinary toilet plungers (the kind with the red-colored rubber cup work best), leaving an inch or so of wood. Then drill a 1/16" hole in the center of the remaining handles. Using a screwdriver inserted through each of the larger holes, attach the plungers to the outside of the tube with a pair of 1/8" stainless screws. Moisten the lip of the plunger cups and force the tube against the smooth surface inside your cockpit. This gadget may slip a little in heavy seas, leaving the lower end resting on the deck. Before beginning construction, measure your cockpit surfaces to tailor the tube's measurements to your needs.