SL3-SWM cover question

[nucklehead]

I've been doing a lot of research on these SWM 3 lnb's and can't seem to find the answers. One lnb has a clear bubble cover and the other a plain white cover. Does anybody know the difference the cover makes?? Looking for the best reception in northern Canada.
Thank you

 

[Mr Tony]

no difference...

 

[Daddy Dithers]

Canada?