Glow in the dark woofer horns are not only great for communicating in the dark theyre great for festivals and big events and for cheering on your favourite sports teamr r each glow woofer horn is large 36cm long and features a loud reed trumpet hooter to blow through want to get your point accross punctuate it with a blast on your wooferhornr 36cm long wooferhorn6cm diameter hornglow wooferhorns glow brightly in the darkglow woofer horns glow under uv or blacklighteach woofer horn in