Im going to stick me neck out and say same as cats eyes on roads?

That or they are very strong.

Where was the pics taken btw?

Oh right so its just like cats eyes then but with lights instead off car reflections:D

At PIK the runway edge lights are on stalks, except of course where the links join the runway and at the turning area at the 31 end.

So will it do damage if a plane went over them?

Regards
James