Back Length: From the bottom of the collar to the hem of the garment.
Sleeve Length
(crown to cuff): From the top of the sleeve to the end of the cuff, with a straight arm.
Shirt Chest Size: Measure around fullest part of your chest. Keeping the tape just under your arms, extend around your shoulder blades, holding tape level.
Helpful and good website. Out of stock item managed well reaching me in time for event as requested.