Purchased to cosmetic needle with. Have had zero issues with any of the cartridges. Not generic quality, same packaging and quality that came with my A6.
These fit my Dr. Pen A6s, but are a pain to get on properly and usually break when taking off. They don’t slide into place easily and I often have to get pliers to remove the cartridge.
I have saved thousands micro-needling at home. These with pen work as well as dermatologist. Please check depths so you do not go to deep in thin areas and cause scarring. Always work under sterile conditions, and use proper aftercare.