The 510-4 4 inch Cylindrical Bidirectional Baffle Enclosures are identical to the 410 series with the addition of a circular mounting canopy complete with mounting hardware and second grille to enable bi-directional sound dispersion. The 510-4 mounts a standard 4" (102mm) loudspeaker. The aluminum housing is patch-jute lined and undercoated to allow clear, audible loudspeaker performance by preventing mechanical and acoustic resonance. One grille per unit includes studs for convenient loudspeaker mounting. The complete assembly installs to a 4" (102mm) octagon E.O. box (by others). Finished in satin brushed aluminum or textured white (W) epoxy where noted.