I have found the answer to my question; it is 'yes'.
The amount of fentanyl released from each system per hour is proportional to the surface area (25 mcg/h per 10.5 cm2). The composition per unit area of all system sizes is identical.
Dose* Size Fentanyl Content
(mcg/h) (cm2) (mg)
12** 5.25 2.1
25 10.5 4.2
50 21 8.4
75 31.5 12.6