Stock up on Quality Canning Jar Lids Engineered to be the highest quality lids available, these regular-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). Locally made in Ohio! BluSeal Integrity - More sealing power and designed to prevent buckling. Safe for high pressure canning.. QuinTek Protection - Five layers of protection. "Pop" Lok Assurance - Distinctive "popping" sound ensures seal. More vacuum, longer-lasting seal.. For Regular Mouth Canning Jars - 2-3/4" outer diameter, lids fit regular-mouth canning jars.. Made in America - USA made in Ohio. 240 lids included. Helpful Hint: When tightening the ring prior to canning, it is important to tighten it, but not make it too tight because over-tightening the ring will not allow the jar to seal properly.An easy way to ensure that the ring is the right tightness - use the three-finger method. Using only three fingers prevents you from over-tightening.