Alright, another stock-by-attribute question -- unfortunately I think I might already know the answer, but I want to double-check!

I have products with multiple attributes. Can I stock by only one of those attributes?

For example, we have titanium barbells in different lengths. Our stock number should be associated with the length. We also, however, custom-anodize these pieces, so we have an attribute drop-down for titanium color options. Is there a way to stock by the length, but NOT by the color?