Those look great! I think I am confused on the question.

Love it. Do you mean the white trim piece under each step? Why would you need to cover it?

Yes- the old moulding is cracked on some ; and there is a gap that needs to be covered.

i need to measure & have something cut at Home Depot.

Also need to paint!

Those look great! i will get a picture of ours so you can see what we did . We removed stapled carpet and pad and the ugly strip was showing. My contractor pulled it off and put on this trim on each step with his nail gun … tiny nails. Painter caulked and painted. looks great.

Edited to add when I expand your picture the tack strips look like what we had . They can’t be redeemed in my experience. The new molding will finish your beautiful project perfectly.

This is how ours looked with the tack strip still there.

Looks great! can you use wood putty and caulk on the moldling you presently have and than paint?

I got some moulding that I think should work (after getting to HD the first time with no wallet!)

You ’nailed it’ C, it is carpet tack from the previous owners. Guess I should’ve removed it, but too late now!

Haha…. that molding is beautiful. will look wonderful with your design. It didn’t occur to me to get anything pretty since we were painting it. Great choice. c

Is the moulding in question that thin white strip under the front of the treads?

Yes Bunny, turns out it is carpet tack.