I have only tested the operation after purchasing it new. I have confirmed that it can be used with flat 2-pin earphones. This is the C16-5, a wired earphone replacement cable from NiceHCK. It has TFZ connectors and a 4.4mm plug. The TFZ connector is compatible with flat-type 2-pin connectors. I plan to ship via Yu-Packet Post Mini. No one in the household smokes. We do not have any pets. I don't have many items for sale, but I welcome combined purchases. If combined shipping is possible, I will discount the shipping cost savings.