Why is the rent on my vent so exorbitant?

We received this question this morning at cycledork central:

Dear Cycledork,
Why do some helmets cost $30 and others cost $200? What's the difference? Aren't they all made of basically the same stuff as a beer cooler?
lady macsquish

Dear lady:
For the same reason that air-conditioning devices range so significantly in price: mass and efficiency. The helmet on the left has 17 comparatively tiny vents and provides all the comfort, in terms of weight and air circulation, of wearing an anvil. The Bell Women’s Bella Sport, now on sale at performancebike.com, costs $22.99. The helmet on the right, a Giro Atmos, has 26 comparatively humongous vents, all of which are larger than the vents on the Bella Sport. It weighs 275 grams, or about 10.5 ounces. Imagine wearing air-conditioned feathers. Plus it offers the same safety as the Bella Sport. The Atmos, now on sale at performancebike.com, goes for $134.99.

Though this is beyond the scope of you question, all of that said, the Bella Sport is the better tool for someone who isn't going to be riding very hard for very long, say no more than 15 mph for an hour or less. For racers or others who are cranking out miles for hours at a time or who feel the need to take every advantage, the cost for comfort or fewer grams becomes worth considering.

And I'm glad you mentioned beer coolers. Beer is close to my heart and never far from my thoughts. It is my hope that bikes and beer is a topic we return to many times in our dogged pursuit of cycling truth.
Yours in velophility,
Cycledork