These Cold Activated caps are a nifty way to cap your bottles! The caps turn blue when they are cold. The caps start to change to blue at 46.4 degrees and at 41 degrees they are at their maximum blue tonality indication. They also have a oxygen absorbing liner. Enough for a 5 gallon batch using 12 oz bottles. 26 mm.

Important to note: It is recommended that you only sanitize as many caps as you'll require at the time of bottling. The oxygen-absorbing agent is activated when the cap gets wet. If wetted caps are saved for later use, they'll still function as a normal cap, but the oxygen absorbing agent may be depleted.

Cold Activated Oxygen Absorbing Bottle Caps