MSA Inhalation Valve Kit Advantage 420 Part Number: 10097883SKU: MSA10097883 Call for Price Clear Options Add $250.00 worth of items to your cart to qualify for free shipping. Item Details MSA Valve Kit includes two inhalation as well as one exhalation valve and is designed to use with 420 half mask respirator. Includes (2) exhalation and (1) inhalation valve