Please do not say "Black shoulders". Does anyone have pictures so I can see the difference? I have what I was told on here by several extremely helpful people with a LOT more knowledge than me (not hard) that mine are IB. A lady wants to sell me her BS IB male which looks JUST like mine???? I do not notice any differences. Is it difficult to see or completely obvious? I also don't want this one, who is older, bullying my beloved lone male who free ranges with his mate. Worried about upsetting the apple cart... Hmmmmm.