Identify pill: U 159 White and Round, other side has +, dividing it into 4 sections?

Spot on!

Pill image and info on the muscle relaxant for future reference:

https://www.drugs.com/imprints/u-169-20752.html

Thanks. Using a magnifying glass, I see that it is U 169! The top of the '6' had a straight line just like a '5'. I used a magnifier the first time, but w/o a spotlight. It was 2 pills I found above the sink, no idea who left them there. Must have been a long time ago, bc I have very few visitors. Luckily, I'm not taking any meds at the time, or I could have accidentally taken those. whew!