Heat Transfer Products (HTP) manufactures high-efficiency boilers, water heaters, and indirect tanks including the Elite, UFT, and Phoenix product lines. The Massachusetts-based brand competes head-on with Lochinvar in residential and light-commercial hydronics.

Huntington Brass produces decorative kitchen and bath fixtures including faucets, shower trim, and accessories in a wide range of finishes. The brand serves designers and showrooms specifying mid-to-high-end residential plumbing.

Husky is The Home Depot's professional tools and storage line, including pliers, wrenches, screwdrivers, and tool storage. Its lifetime-warranty hand tools are widely used by plumbers, electricians, and other tradespeople.

ICM Controls manufactures HVAC and refrigeration controls including head-pressure controls, defrost timers, hard-start kits, and motor-protection modules. Its boards and modules are common service replacements for furnace, heat-pump, and refrigeration equipment.

Imperial Manufacturing Group produces HVAC accessories including pipe and duct fittings, dampers, range-hood ducting, and chimney accessories. The Canadian-headquartered company supplies HVAC wholesalers and home centers across North America.

Jaclo manufactures decorative bathroom and kitchen plumbing including showerheads, hand showers, body sprays, supply lines, and exposed-style trim. The New Jersey-based brand is favored for its broad finish library used in mid-to-high-end residential builds.

K-Rain Manufacturing produces irrigation rotors, valves, and controllers for residential and commercial sprinkler systems. The Florida-based brand competes with Hunter, Rain Bird, and Toro across the irrigation distribution network.

Kallista, a Kohler Co. luxury brand, designs handcrafted bath and kitchen fixtures including faucets, lavatories, tubs, and shower fittings. Its collections, often by named designers, target the high-end residential and yacht markets.

King Innovation makes irrigation accessories including DryConn waterproof wire connectors, valve boxes, and tools for splicing and installing low-voltage controls. Its waterproof connectors are standard issue for irrigation contractors.

Kohler Co. is one of the largest plumbing manufacturers in the world, producing toilets, sinks, faucets, baths, showers, and accessories under the flagship Kohler brand and luxury offshoots like Kallista and Robern. The Wisconsin-headquartered brand sets benchmarks across kitchen and bath.