Ball lids provide airtight, leak-proof designs in several ways: one-piece screw-on lids that compress a gasket, lids that form an airtight silicone seal, and some wide-mouth replacement lids that include a pop safety button to quickly check the seal (button depressed when sealed, will pop up if the seal fails).
Listings typically state compatibility by jar mouth type (Regular Mouth or Wide Mouth) and/or give diameter measurements in inches or millimeters (for example, 3.31 in / 84 mm or 86 mm) so you can verify fit with your jar bands.
Some lids include a pop safety button that stays depressed when the jar is sealed and will pop up if the seal fails. Product descriptions and reviews also commonly note reliable, leakproof seals; a popped button or an obvious pressure change in the lid indicates a failed seal.
Listings show Regular Mouth and Wide Mouth options. Product details commonly list neck diameters such as 2.75 inches, 3 inches, and 3.5 inches; some wide-mouth replacements are also listed using metric measurements (about 84–86 mm).