FITS STANDARD REGULAR-MOUTH MASON JARS - Designed for the everyday mason jar shopper. Slide-port drink lid fits standard regular-mouth mason jars with a 2 3/4 inch (70mm) outer rim - Ball, Kerr, Bernardin, and most regular-mouth jars manufactured 2015 or later. To seal correctly: press the lid straight down until the rim flange seats flush against the jar threads. WIDE OPENING - SIP DIRECT OR INSERT A STRAW - Slide the port open with your thumb for a direct sip, or insert a standard 6-10mm reusable straw. The straw port is sized to accept and hold a straw upright; it is NOT a sealed straw lid. Inner gasket is permanently molded and made from food-grade TEO (thermoplastic polyolefin elastomer) - not silicone. USA MADE FROM FOOD-SAFE, ODOR-FREE POLYPROPYLENE #5 - Made in the United States from BPA-free, phthalate-free, BPS-free polypropylene #5 with a food-grade TEO inner gasket. Odor-free and taste-neutral. (For freezer storage, use iLIDS Wide-Mouth Drink Lids - regular-mouth jar necks can crack from contents expansion.) TOP-RACK DISHWASHER SAFE - NOT MICROWAVE SAFE - Drops in the top rack with your tumblers; bottle-brush the gasket channel once a month. Won't rust, dent, or warp like metal canning rings. Not microwave safe - for food safety, never heat plastics in the microwave. PACK OF 2 IN 15+ COLORS - BEST FOR UPRIGHT DAILY USE - Two lids cover a home-and-office routine. Best for desk, countertop, car cup holder; if you need a fully sealed travel container, a dedicated travel mug is a better fit.