Hi, is it ok to use m5 allen key bolt instead of the pan head type described in j442 ? " Use pan head (or smaller head diameter) style screw of size M5."

The allen key bolt has a smaller head than a pan head.

/R

google search bolt Picture

Changing the head type is fine as long as the head isn't larger, thus causing an excessive "shaded" area.

EI uses hex (Allen) screws in their products. Recently I heard someone report that star (Torx) heads have a longer life span than hex style.

The heads height is not defined in the spec. Is it then ok to use the cylindrical bolts that I linked to as long as the diameter is smaller than a typical pan head and its not leaving an excessive shade ?
I think the hex or torx is muche more user friendly as you say.

Just be careful of heads that are too tall, as they can shade when the blast stream comes in at lower angles.