I was given a whole bunch of n:vision 65 watt "high quality flood" lights, still in their packages. I don't have much use for them in my house, but I could sure use them for my yard lights. How can one tell if they are suitable for outside use?

It should say outdoor use on the packages. Also look to see if it is watertight, maybe comes with a gasket or something.

Outdoor lights have thicker glass to withstand cool rain water hittng the lens and cracking it. You can tell the difference in weight and in feel.

Jimmy