The HDT Lightweight Environmental Control Unit (LECU) is a 60,000 BTU/H (17.6 kW) Improved Environment Control Unit (IECU) that operates in a chemical, biological, radiological and nuclear (CBRN) environment and is compatible with such Joint Project Manager Collective Protective equipment as Collectively Protected Field Hospitals (CPFHs).

The US Air Force qualified the HDT 60K LECU for use with its Expeditionary Medical Support (EMEDS) program and the unit also functions with Army and Navy field hospitals. The LECU offers a high-pressure blower, phase protection, and optional continuous run (hot gas bypass). Field users favor the LECU for its simple, rugged design and easy maintenance and the small size and light weight allow 16 LECUs to fit onto a single 463L pallet.