I could have told you that. The VME bodies are designed to work with their heads to hold a Malkoff drop-in. The bodies are about 1/4" too short and SureFire E-series heads require this additional space or else you won't get things to thread together. If you drop a battery into a single-cell SureFire E-series light (or two batteries into a two-cell light) you'll notice that the top of the battery sits about 1/8" below the top of the body. If you drop a battery into a single-cell VME body you'll notice that the battery sits above flush with the end of the body and you cannot push down on the battery much beyond flush with the body tube before the battery bottoms out in the tube.
I will add that the first gen VME CR123 body will work with an E1B head as it was a two piece body and it could be adjusted for E series heads or Malkoff drop-ins in VME heads. I own a first gen VME CR123 body.
