anyone fitted these before ?

i was planning fitting some to a wooden staircase going up to an attic
the staircase is about 800mm wide,it is for light when the kid comes down from the attic in the night for the toilet, so he dont fall down the stair

i seen some 15mm diameter ones and planned on fitting one per step. do you think these will give of enough light in the dark ?
there will be 10 in total

The 15mm diameter ones might not be bright enough.

You would prob be better going for 30mm or 50mm ones

I have fitted loads