Cubby Buddy 124DA Add-On toolbox is exactly the same as Cubby Buddy 124D, measuring 5 1/2"H x 11"W x 24-1/4"D, but without the mounting cradle. This one drawer add-on model fits easily atop any of our base models (224, 220, 124D and 120D) or atop any of our add-on models (224A, 220A, 120A, 124A, 124DA, 120DA)