Stock up on Quality Canning Jar Lids Engineered to be the highest quality lids available, these wide-mouth canning lids have a specially formulated adhesive that is thicker and wider to seal on virtually all jars (always follow USDA recommendations when canning). USA made in Ohio. BluSeal Integrity-More sealing power and designed to prevent buckling. Safe for high pressure canning.. QuinTek Protection-Five layers of corrosion protection.. "Pop"Lok Assurance-Distinctive "popping" sound ensures seal. More vacuum, longer-lasting seal.. For Wide Mouth Canning Jars-Lids fit wide-mouth canning jars.. Made in America-USA made in Ohio.. Helpful Hint: When tightening the ring prior to canning, it is important to "tighten it, but not make it too tight" because over tightening ring will not allow the jar to seal properly. An easy way to ensure that the ring is tight, but not too tight, is using the three-finger method. Using only three fingers prevents you from over tightening the ring.