This black anodized aluminum louver is composed of a honeycomb pattern of dividers. It cuts out stray light (glare) past about 45 degrees from the beam center.

It also hardens the beam edge slightly and accentuates the hot spot.

It decreases center beam brightness by about 30%.

It's main use is in controlling glare. Typical scenarios would be to shield glare from fixtures in planting beds that are near walkways or driveways; or in cases where light might otherwise spill into windows.

Download IES file of CAST MR-16 Bullet Light with CXL louver

CAST MR-16 Bullet (no Filter/Lens)

CAST MR-16 Bullet (with CXL Louver)