| Description | QC7I Quad Parallel Head, quad. filter head, parallel plumbed with shut-off and flushing valves, inlet/outlet pressure gauges | QL1 Single Head, without shut off, includes bracket & 3/8" NPT, for use with 2-size or 4-size filter cartridges only (MUST BUY IN MULTIPLES OF 24) price per each | QL1 Single Head, without shut off, use with 2-size or 4-size filter cartridges only (MUST BUY IN MULTIPLES OF 24) price per each | QC7I Twin Parallel Head, dual filter head parallel plumbed with shut-off, flushing valves and outlet pressure gauge | QL7I Triple Parallel Head, triple filter head parallel plumbed with shut-off, flushing valves and outlet pressure gauges |