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Brad's Deals Editor Jacob,
This High Altitude Simulating Training Mask is going for $9.99 at Ofshop via Amazon. Shipping is free for Prime members or when you spend more than $25. Otherwise, it starts at $5.99. Similar products are going for at least $15 elsewhere. It adjusts to 48 different resistance levels between altitudes of 2,000 to 18,000 feet. Sales tax is charged in most states.