Abstract: A mounting plate for detachably fixing a heavy duty, normally permanently attached, swivelling base plate caster roller unit to an object to be transported is cut from an extrusion shaped to form a flat bottom plate with raised parallel sides each including an overhanging flange such that parallel grooves are provided into which the caster's swiveling base plate can slide. Attachment of the mounting plate to the transportable object utilizes at least two mounting pins (screws, bolts or rivets), at least one of which protrudes from the mounting plate inside surface to form a stop to prevent the swivel plate from sliding all the way through. A spring loaded button, which becomes flush with the mounting plate when depressed, allows the caster swivel plate to enter the cavity provided by the parallel extruded grooves and the protruding mounting stop.