Consolidation of Products on Website

I have some questions regarding products on my website. When we first signed up with E-Commerce, we had someone manually enter our products on the website. My problem is that some of my products from the same manufacturer are essentially the same thing besides a certain length or a certain width. For example, we sell Bobrick grab bars at three different sizes. I want to add a drop down list so the customer would go to Bobrick grab bars and be able to select from a drop-down list of the different sizes. Much like you would if you were a shirt or shoes online (you would have a drop down for the different sizes). I think this would clean up the look on my website, and be more user friendly. Is this possible with e-commerce?

sperry wrote:
You can do it with product variant attributes.
Check example of etnies-mens-digit-sneaker in front and back ends

Thanks Eduardo

I think I am almost there, Is there an easy way to link products to each other. Or do I have to go into one of the products and insert each product variance individually? I am still having trouble figuring out the drop down bar, I can only get the variants to show on the same page.

Thanks for the help