I've been on Estraderm MX 75 for over 2 years now, I find them brilliant. They are the only patches I can tolerate and absorb. They are an older estrogen patch that's been around a long time. My Aunty has been on them for decades.
I don't know what type of estrogen they contain, but I presume it's a body identical one. It's the only form of estrogen I can take as gels, tablets and other patches all give me daily chronic migraine.