Okay, if you're tired of mismatched lids or dealing with broken covers, this 12-inch tempered glass lid might be your new kitchen best friend. The inner diameter is about 297mm (11.69 inches) and outer is 312mm (12.28 inches) - just make sure to measure your pans before ordering to get the right fit. This thing is designed to work with pretty much any 12-inch cookware you've got - stainless steel pans, cast iron, cast aluminum, frying pans, skillets, deep sauté pans, woks, saucepans, even Dutch ovens. The tempered glass is way more durable than regular glass, with shock-resistant technology so you don't have to worry about it shattering unexpectedly. The wooden handle looks nice and stays cool to the touch. There's an anti-overflow vent that releases excess steam but still locks in moisture and flavor - plus you can actually see what's cooking without lifting the lid! The seamless stainless steel rim creates a good seal, and the smooth glass surface makes cleaning super easy (yes, it's dishwasher safe). You can even use it in the oven - just remember to use oven mitts when handling the hot lid. Honestly, having one quality lid that fits multiple pans can seriously declutter your kitchen and make cooking so much more convenient. No more guessing if your food is boiling over or burning - just glance through the glass and you're good to go!