The adhesive between the A and B surfaces is different. Make sure to stick silicone rubber to the A surface.
Firmly crimp the entire product and leave it in place until it has been pasted for about 24 hours.
Surface A: Not compatible with other than silicone material. B Surface: Not compatible with non-adhesive plastic such as fluorine treated surfaces, textured surfaces, heavy objects, polyethylene, polypropylene.