Regular Black Polymer End Cap; strong recycled UV stabilized polypropylene polymer plastic trench drain end cap; caps off end of any deep trench drain length; the deep trench drain, because of its high-profile design, is ideal for high water flow areas; simply clip end cap into channel trench drain length and it is instantly ready for use as a finishing point with any choice of regular black or steel residential trench drain; the end cap is one of the many accessory options that can be used with our yard drainage systems; other accessories include converter pieces, corner pieces, tee pieces, slim pits, catch basins and stormwater pits; for every 3-pack of regular trench drain you purchase, we include 2 regular black polymer ends cap/adaptors at no extra charge; purchasing the 3-pack is a cost effective way to get more quality trench drain for your money; when the regular black polymer end cap is installed in reverse, it becomes an adaptor piece with a 3” cutout section that can be cut out with a hole saw to add a 3” pvc drainage pipe to the end of the trench drain system; to install a 4” pvc drainage pipe, use a 3” to 4” adaptor piece that you can easily find for a few dollars at your local hardware store; Regular Black Polymer End Cap measures 1.34” x 4.96” x 4.29”.