A diffuser lens printed in clear PET plasic which fits onto the line of Streamlight SIdewinder flashlights. It's pictured on my Compact II, but should fit the heads of any of the models of Sidewinder lights. It turns the flashlight into a lantern which will light up a whole room at once. It just snaps onto the front of the flashlight. It's a tight fit and will not fall off. I have carried my light on my belt with the lens on it all day, no problems.It MUST be printed out of crystal clear material. It looks white in the pictures because when clear plastic is layered in 3D printing, it refracts the light at each layer, giving that appearance. This makes it work very well as a diffuser lens! I used clear PET (soda bottle plastic) and I highly suggest it. PET filament can be bought online. It prints just like PLA, but it's VERY durable, and UV resistant. It's also safe to get gasoline or other fuels on it, even acetone. This is good if you're using it in a workshop where these things are present. I have included the .ipt file in case anyone has Autodesk Inventor and wants to edit it.