We provide a 4-valent ribbon model for SL(4) skein category by working with a category with object an oriented marking and morphisms generated by tagged and untagged 4-valent vertices. The category is defined combinatorially in terms of diagrammatic generators and relations. We use linear algebraic and skein theoretic methods to explore topological invariants coming from such a category. As a consequence, we show that a specialization of our parameters provides a 4-valent category that is equivalent to the SL(4) representation category. We further provide a topological evaluation algorithm of closed webs providing a (topological) criterion for reducible webs. We also show that certain HOMFLY relations exist in our category. Our evaluation algorithm works at a very abstract level and doesn’t use any algebraic constraints coming from the representation theory. This is a joint work with Giovanni Ferrer and Jiaqi Lu.