Take your drink on the go—worry-free! These silicone plugs make our Silicone Straw Hole Tumbler Lids 100% Leak-Proof! (Note: Silicone Straw Hole Lids sold separately.) The durable, food-grade, silicone strap loops around the mouth of the jar and is secured in place by the band. It features an additional loop to hold your straw when not in use, making your jar perfectly portable! Great for kids! No more spills! Food grade silicone rubber is dishwasher, freezer, and microwave safe! Silicone is a safe, plastic-free, BPA-free material that does not leach chemicals like plastic can. Only compatible with our Silicone Straw Hole Tumbler Lids. Will not fit our other tumbler lids. Can fit around regular or wide mouth Mason jars - Ball, Kerr, and other canning jars.