Thumbnail images in single row

[paulhazell]

Vm 2.0.10
Joomla 2.5.8

Currently if i use more than 3 images in a product the thumbnails are displayed in 2 rows rather then spanning across the entire width of the main image.
I have looked at the CSS using firebug but i cannot find any way to change the width of the container without affecting other pages.
The only entry i can see that is affecting the rows is this;

.width50 {
    width: 50%;
}

Is there any other way i can widen the container without changing the value above?

Thanks in advance.