'Invented by Theophilus Van Kannel, these entrances save energy & equalize air pressure in skyscrapers'
revolving doors
EVOLUTION: Invented by Theophilus Van Kannel, these entrances save energy & equalize air pressure in skyscrapers
Invented by Theophilus Van Kannel, these entrances save energy & equalize air pressure in skyscrapers
Invented by Theophilus Van Kannel, these entrances save energy & equalize air pressure in skyscrapers
"EVO"LUTION
revolving doors
"EVO"LUTION