We are terminating pex connections with drop-ear-90s and brass nipples. Should we use stainless screws to mount the drip-ears? If not what do you suggest?
Any screw will work on the brass elbow.
I like to use decking screws, mainly because they are harder then brass, and they are coated to prevent rusting if I use them on the exterior.
Stainless should be fine.
Lifetime polymer coated and zinc plated for extra corrosion resistance. The unique recess drives with the combination driver bit included in each box or drives with a standard #2 square driver bit.