These Seachoice 3-to-1 Heat Shrink Butt Connectors feature premium construction for the best results, and they produce a complete environmental seal. These yellow Marine-Grade heat-shrinkable butt splices feature tin-plated 99.9% pure copper and a seamless tube. The proprietary nylon/polyolefin tubing has a 3:1 shrink ratio and adhesive lining. They provide maximum clarity for wire inspection and also deliver faster shrink times and improved abrasion resistance. These Butt Connectors can splice wires together quickly and easily. Simply insert the wires, crimp the connector, and heat-shrink it for a complete environmental seal. A heat gun or even a hair dryer can be used as a heat source. These Butt Connectors are for 12-10 wire range, and they come in a pack of 100 connectors. Seachoice is committed to delivering quality marine accessories and OEM replacement parts to satisfy fishing, boating and watersports enthusiasts worldwide. Seachoice is run for and by boaters, offering a wide-ranging product line while remaining affordable.