The GRIPSTER is a mixture of a TALON Grip and a Coaster. The Universal Gripster fits most travel mugs and measures 2 11/16" in diameter. YETI Gripsters fit the 10 oz Lowball, 20 oz Rambler, 30 oz Rambler as well as the Colster. If you like hot drinks HOT or cold drinks COLD the YETI Ramblers are perfect unless they scratch your wife's coffee table (true story). With this GRIPSTER you can stop the scratching, reduce sliding, or install a stylish decal on the side of your Rambler to let people know that you support two great companies! One GRIPSTER is included with this purchase.