Glaslock

Tempered glass feels sturdy and hasn't warped after weeks of daily use. The steam stays locked in nicely, so my sauces don't dry out while simmering.

Steam beads up on the glass so evenly that I can watch the sauce reduce without lifting the lid and losing heat. It's heavier than I expected, which makes it sit snugly on the pan rim, and clean-up is just a quick rinse.

Finally a lid that actually fits flush on my carbon steel pan — the tempered glass is thick and reassuring, and I can finally watch my sauce reduce without lifting it every two minutes. The steam trapped against the glass keeps my veggies from drying out on low heat. Exactly what I needed.