Abstract: An adaptor mechanism for use with a skid steer loader having an implement mounting plate configured in a first attachment configuration is disclosed wherein the adaptor mechanism permits the attachment of an implement configured in a second implement attachment configuration to the skid steer loader. The adaptor mechanism includes a movable locking mechanism having hook members protruding perpendicularly therefrom for engagement with the overcenter wedging mechanism in the implement mounting apparatus on the skid steer loader. A spring biases a locking mechanism toward a retracted position; however, engagement of the hook members by the skid steer loader overcenter wedging mechanism overcomes the biasing force exerted by the spring to force the locking mechanism into engagement with the implement being mounted thereto.