It was used to join the angled nubs at the end of of a handrail, and the railing was dropped during refinsihing and the end nub split. A trim carpenter friend of mine called it a spline nail, but no luck finding a source using google. Does anyone know the official name of this? or even better post a link to a place I can buy them. Many thanks!
Also, is this installed using a hammer or is there some air tool required? Any pre-drilling or special prep needed besides clamping? I’m concerned the new nubs would split as well unless there is some form of pre-drill/prep.