The Reactor 3 E-20 is a spray foam system build for contractors focused on smaller jobs or for contractors just entering the business, it is a great starter machine. Due to the smaller heaters the E-20 has, also makes it a good choice for contractors in tempered climates where larger heaters are not required. Reactor 3 is designed to communicate with the entire system to simplify the operator's job, optimize spray parameters and maximize productivity.