Replying to Bern helmet question

k so I was looking at berns website, and for the baker helmet, they say it comes in three models. The winter, summer, and water one. However, if you look at the spec differences between the snow and summer one, I didn't notice a difference. Also the weight listed is the exact same for both summer and winter, but there is a $40 price difference. Is this cause the winter one has a built in beanie that is detachable? Cause if so couldn't I buy the summer one and just use a beanie I already have? Or does the snow one have additional safety stuff. Sorry for the long post, and info would be awesome