PRM

Perimeter Solutions, Inc.

A maker of wildfire-fighting chemicals and specialty products, Perimeter Solutions supplies the PHOS-CHEK and FIRE-TROL retardants dropped from air tankers to slow blazes, plus phosphorus-based lubricant additives and machinery for medical device manufacturing. The company took its current form in 2018 when private investor SK Capital bought these businesses from Israel Chemicals, though the PHOS-CHEK brand dates to a 1960s Monsanto invention first approved by the U.S. Forest Service in 1963 — its name combines the phosphate chemistry with its job to "check" the spread of fire.