WORKS WITH WIDE MOUTH MASON JARS: Designed to fit all wide-mouth mason and canning jars (Bell, Kerr, Bernardin, etc.) Wide width is 3.38 in or 8.6 cm.CHILD RESISTANT: Make any regular size mason jar child safe. This lid features the same push down and twist locking mechanism as standard commercial pill bottles.HANDY DIVIDING TUBE: The Jar Safe comes with an inner dividing tube (3.5" long & 1.9" wide) that can be secured to the bottom of your lids. The organizer tube provides a way to separate a combination of items and makes it easy to see what's inside & where.MULTI-USE: Inner Tube can be used for delicate items or removed for more jar storage spaceAIRLOCK GASKET FOR FRESHNESS: The Jar Safe features a silicone gasket in the lid to prevent air from entering or escaping the jar.DISHWASHER & FOOD SAFE: Like all Masontops products, your Jar Safe is made from 100% premium quality food safe plastic and silicone. They are completely BPA-free and contain no phthalates. Your Jar Safe is made from durable and premium quality materials, so it's tough enough to last for years and goes right into the dishwasher.AWARD-WINNING BRAND: Masontops focuses on making accessories for Mason jars, with a special emphasis on health and wellness. Founded in 2014, Masontops has been recognized as Canada’s 8th Fastest Growing Start Up and has since grown to offer hundreds of different products under the Masontops, Breadsmart and Dinneractive brands.