The original roof mount swept-back radio antenna can be a problem, but isn't easily circumvented either.
Is the anyone out there among this HHR enthusiast group that has experience with the linked-to product, or a known workable alternative?
Although the OE antenna might be the best overall, I dislike the difficulties arising fpr all sorts of scenarios, high on that list: using a car cover.

 

Use a stubby antenna

 

The antenna mast is removable. It unscrews. Just take it off if you want to put on a car cover.

 

I opted for this:
Votex Black Short Rubber 6 3/4" kit-Flexible. - It knocks 8-1/2" off the original's total length, so there's that.
rather than utterly concerned with lowest profile, the 'shorter' -plus- flexible meant more to me.
The company touts itself as an American company, AND, it comes with a bag full of stainless steel adaptation male-to-male couplers that would allow the antenna to be transferred to a huge number of alternative applications.
It -might- be less likely to be stolen, since it doesn't sport the premier company's branding, and it's a bit less expensive too.