NordicTrack women's 1/4 zipper long sleeve shirt thumbholes back pocket

NordicTrack women's 1/4 zipper long sleeve shirt thumbholes back pocket Has thumbhole on each sleeve has back pocket - I was told the stitched hole on the back pocket is to clip on something. There is no button Size M please measure to ensure proper fit armpit to armpit about 18 shoulder to hem about 24 sleeve from collar to wrist - rather long 30 pocket about 4x5