This is a SolidWorks model of my flashlight concept, with the directional shade down.
My target customers need a flashlight that is durable. I would use anodized 6061 aluminum alloy for the body, end cap, switch, and shade. This aluminum alloy is light, durable, and inexpensive. For the window that protects the LED and supports the directional shade when up, I would use Lexan. This is a durable, clear, plastic material. The popular, durable Maglite flashlight uses these materials also.