Marley Engineered Products introduces the out-of-sight, out-of-mind UL-listed in-floor perimeter convector — THX Series heater, which delivers comfort, aesthetics and safety for the ultimate supplemental heat system for both new and existing buildings, the company notes. Offered by QMark and Berko brands, the THX Series directly addresses the building’s need for supplemental heat against the curtain walls and glazing, while fully integrating with the architect’s designed interior spaces. The unit drops directly into the floor, leaving only the grill visible for unobstructed sightlines and more design space with which to work, Marley adds. Marley Engineered Products.