I'm looking for a 510 passthrough with no battery box. A true 3.7v device would be nice. I might also be willing to try out a 5v passthrough but I'n not sure on that one. I remember seeing a supplier that sold a 901 passthrough with a 510 adaptor for a very reasonable price but I don't remember who it was. I need something to replace my dieing joye 510 passthrough. Thanks in advance.