Latch T compatibility is currently based on 2 constraints; physical compatibility, and frequency compatibility. Physical compatibility requires that the Latch T satellite can be attached with adhesion to the surface of the legacy reader. You may need to use the temporary adhesive to find the correct location for the satellite as different readers have different placement requirements. Latch T’s frequency compatibility is with low-frequency (125khz) readers, if your device is high frequency, it will not work.