Aluminum fasteners are difficult to find and these are great. I use them as cleats on studded wading shoes and they are easy to install, reasonably durable, and give much better grip than steel or standard carbide studs. Most carbide studs have very small tips and tend to release unexpectedly on big smooth surface rocks. The surface area and softness of the aluminum allows for a much larger and stickier grip.Just remember that aluminum is softer so use the right size screw driver and pilot hole. Perfect for my use - retro-fit of continuous aluminum soffit vent. Old vent was painted closed.This screw weighs 1/3 of steel screws and does not rust nearly as quickly, yet is strong enough for most applications.Heads break off with almost no torque. A complete waste of time and not worth returning them. BUY SOMETHING ELSECame on time and as describedPretty much as expected, a nice aluminum screw.