AIRSOFT SIGHT KILLFLASH
The Kill Flash is an Anti-Reflection Device (ARD), specially designed to eliminate potentially compromising reflections that give away your position.
As well as this, the honeycomb design also protects the lens from BB impacts, scratching and sun glare whilst still allowing for a bright view, without interfering with the targeting.
The Kill Flash simply screws into (or plugs into) the existing threads on the front of your scope, and so still allows for the use of a lens cover.
The honeycomb design will reduce the amount of light entering the sight, so possibly not suited to use in low-light conditions.