The BlowTie 2 Spunding Valve complete kit is used to release excess pressure on a pressurized fermenter or from a keg while doing pressure transfers. Thanks to the large surface area of the diaphragm, this style spunding valve is much more accurate than the poppet style. The blow off pressure can be easily set using the BlowTie's integrated pressure gauge. The kit includes everything you'll need to use the spunding valve right out of the bag.