In the 1990s Johnson introduced the new 'Ultimate' series which consisted of the same flap assembly with a much sturdier extruded aluminum frame and steel locking cover to replace the old fiberboard one. Fit and finish on this door was very nice.

Later, Johnson introduced the 'Tuffi-Dor' also known as the Pet Door Jr. This was, again, the same flap assembly but a white or brown polypropylene frame.

In the late 1990s, Johnson Pet Dor was acquired by Radio Systems Corporation, which also acquired US Pet Products at about the same time. The Johnson trade mark still appears but Radio Systems emphasizes their 'PetSafe' trademark as well. Radio Systems discontinued the Johnson Patio Panel in favor of a redesigned version that incorporated the US Pet Products flap.