the calibaration kit has 1 use. calibrating hygrometers. it calibrates your hygros with a small 75.5% humidipak. The bag itself is airtight, and great for small hygrometers. only drawback is the bag is small, so some of the larger hygrometers wont fit. if you have a large hygro, Then you can use a Boveda to calibrate. I like using a Boveda in a small, clear, plastic kitchen canister. make sure the canister has a gasket and a clamp down lid so you get a tight seal. do a 48 hour test. Accurate as can be. Advantage of the Boveda is that you could also use it in a travel humidor, as well as using it to calibrate.
Throw away your salt and bottle caps. The salt test is obsolete. This is your best calibration method.
