Word to specify short in the longitudinal sense only

I’m writing a text about rectangular plates (skirts) that are mounted to semi-trailers, as shown in the image below:

Source

In the text, we want to emphasize that our products are shorter (in the longitudinal sense) than those used before. At the moment we describe them as ‘shorter’, but we got feedback from our proofreaders that they associated ‘shorter’ with the vertical length (height).
I thought about ‘shorter length’ skirts, but I’m wondering if there is an alternative. I repeat this feature several times, so it would be good to have some alternatives to avoid word repetition.

Is there a way to describe ‘shorter in the longitudinal sense’ in a brief way?