Paper leader and trailer, like 220, I think, but I'm not sure. Again as far as I recall, Contaxes (and presumably Exaktas and anything else that could handle cassette-to-cassette with standardized cassettes) could be used with something similar (i.e. no cassette). I have read that it was a standard load from some manufacturers, though not cross-compatible with Mercury. And no, I'm not confusing it with daylight reloads for standard cassettes (paper leader only).