There are a few products out there that are used to accomplish this same purpose. They differ in material and how they’re attached. I have used some in the past that were plastic with a screw lock spring that you screw down into the nose of the swimbait. But the Halo Coneheads are actually made of rubber and can be attached to the line in the same way that a bobber stopper is attached. The Coneheads come in packs of eight consisting of two sets of four Coneheads attached to two plastic disks. There are thin wires that come up from the disk, go through each Conehead and then double back through to form a loop in the wire.
Before you tie on your swimbait, you want to take your line and run about three inches of it through one of these wire loops. Then, pull the Conehead associated with that wire loop up off of the wire and onto your line until the tag end of your line comes through the bottom of the Conehead. Now you should be left with one of the Coneheads on your line and enough line below it to then tie on the hook for your swimbait. If you need a little more line to work with, simply slip the Conehead up your line a bit. Once you’ve tied on your hook and rigged up your soft plastic swimbait, simply pull the Conehead down and snug it up next to the bait.