PHRESH CARBONAIRE DUCT SILENCER'S   4" X 12"
PHRESH CARBONAIRE DUCT SILENCER'S 4" X 12" at HorticultureSource.com -
Phresh Duct Silencers Sound reducing acoustic foam decreases fan noise by up to 50%. Attach to inline fans used with Phresh Carbon Filters, cooling light systems and more. Durable and light weight aluminum body. Compact size is easy to install. Attach a Phresh Silencer to the intake or exhaust side of an inline fan. Use on both sides for maximum sound reduction.