What's the button thing/switch on the dash for?

Here's a blow-up of another online photo I found, switch labeled 'top":

View attachment 1715913734

Interesting that the top switch and the black plastic bezel around it (with white lettering) is in the style of 63-64 dash switches. It doesn't match the 65 Valiant/Barracuda switch style at all. Guessing that Chrysler didn't want to bother tooling up for a top switch in the 65 style for the limited run of 65 Valiant convertibles.