Bootstrap puts borders around images

Please look at http://autowaterinc.com/services_rf.html.

Note that the images that are "pull-left" have borders put around them that are not there in the raw image.

For example, see last (bottom-most) image attached. It is also fascinating how Bootstrap enlarges the raw image

How can I avoid this?

Thanks

It is also fascinating how Bootstrap enlarges the raw image.
winter.gif