Transparent Dials

I’ve noticed that WD’s main webpage ( has transparant directiondial.gif and gustdial.gif images. Those images have a colored background on my page. How do I make them transparant on mine?

i set the background color as white
go to setup, ftp/internet setup,custom web page, and scroll down to see where to set the background colour there of each individual dial image

That worked Ok. I was able to match my background good enough, using custom colors. Thanks for the help!