A few photos of parts I can't identify
 

Hi, I was wondering if someone (s) could help identify a few parts on my
W115 300D.

The first one is a box on the driver's front fender. It has a rubber push button switch.

The second one is just in front of the passenger on the firewall.

The third is a round pedal.

Thanks!

Mark

1) relay
2) a/c drier
3) foot operated washer pomp

Thanks doc, can you tell me what the relay is for, and why the button, and what does the AC drier do?

Mark