The American black bear lived during the same period as short-faced bears (Arctodus simus and A. pristinus) and the Florida spectacled bear (Tremarctos floridanus). These Tremarctine bears evolved from bears that had emigrated from Asia to North America 7â8 ma.
A plenum space is a part of a building that can facilitate air circulation for heating and air conditioning systems, by providing pathways for either heated/conditioned or return airflows, usually at greater than atmospheric pressure.
Plenum Rated Unit Heaters. Plenum Rated Unit Heaters Are Used In Concealed Areas Of High Rise Commercial Buildings, Concession Stands, School Bathrooms, Large Lobbies, Foyers Or Entrance Ways And More. Plenum Rated Unit Heaters are constructed of rugged powder coated steel for long lasting durability and reliability. Use to pre-heat outside air.