All I know and what I have passed on is what I have heard and seen with the Cee Baily windsheild. I have no part # to compare, but I can tell you this, the Cee Baily shield does fit the stock RG and does not fit the 09 SERG even without trying to use the stock 09 SERG rubber gasket, I have a friend with a 09 RG that used the Baily shield and it fit fine, on mine, it did not fit right, Cee Baily is aware of this and is making windsheids for or 09 SERG. If someone has a parts book and numbers to compare I would be very interested to know myself if in fact the 09 SERG has a differant part# for the outer fairing than the stock 09 RG. I find it hard to beleive myself they would be differant but we may just have a prototype for the future line of RGs, as the 09SERG gasket is far better than anything HD has produced so far. Doc