That price went up.
At the start of the month, that box of 4 for Pacer was only $4.99. I picked up two cases.
I have been hesitant to get the RainX stuff because I go through a LOT of fluid. I'm on my 2nd bottle in the case this month. I tend to use RainX treatments whenever (such as the de-icer) and use the cheap blue stuff to get me through.