Home › Forums › Stay Dirty Lounge › Service and Repair Questions Answered Here › 94 Silverado C1500 Air Distributor › 94 Silverado C1500 Air Distributor January 6, 2020 at 2:47 am #895671 NelsonParticipant The hvac box sealant tape you need is a butyl rubber sealant tape. It comes on a roll Example is the Model 40BT , made by Fabral and sold by Home Depot. You will need to identify the width for your application.