Measurements of the [Formula: see text] production cross-section at [Formula: see text] in proton-antiproton collisions were performed by the CDF and DØ collaborations using [Formula: see text] final states where both W's decay hadronically. Each experiment uses luminosity of about 160 pb-1 of data collected during Run II of the Fermilab Tevatron collider. Beside kinematical observables both experiments take advantage of identifying b jets based on lifetime tagging. While CDF counts the number of b-tags over background after a cut based analysis, DØ counts the excess of events after a neural network based kinematical selection and requiring a b-tagged jet. CDF obtains [Formula: see text]; [Formula: see text].