You can never have too many lids! Swig slider lids are perfect if you prefer a more secure, splash-free option. Check out the care instructions regarding how to remove the slider for better cleaning. The lid is BPA free, dishwasher safe and secures to the cup via a push-seal silicone gasket. The clear lid design seals tightly to minimize spills and maintain temperature while allowing you to see inside. It also features a straw friendly opening. Small (2.75" diameter) fits: 12oz Skinny Can Cooler Medium (3.0" diameter) fits: 12oz Wine 14oz Wine 12oz Combo cooler 20oz Tumbler (with silicone base) Large (3.5" diameter) fits: 18oz Mug 22oz Mug 22oz Tumbler 12oz Lowball XLarge (4.0" diameter) fits: 40oz Mega Mug 32oz Tumbler 8oz martini