Pure Water Products produces two types of water filters. One attaches to the faucet and cleans all water that passes through the faucet. The other is a pitcher-filter that only purifies water meant for drinking. Revenue and cost information for each product appears below:

the unit that attaches to the faucet is sold for $70 and has variable costs of $30

the pitcher-filter sells for $80 and has variable costs of $45

fixed costs total $424,000

Pure Water sells 4 faucet models for every 3 pitcher-filters sold

Calculate the number of units of the pitcher-filters that must be sold in order for Pure Water Products to break-even.