940720bm.zip contains 3 files:

bm940720.zip = BM smtpmailer for NET/NOS MSDOS version
bm0720lx.zip = BM smtpmailer for NET/NOS Linux version
bm0720sn.taz = BM smtpmailer for NET/NOS SunOS version (bm0720sn.tar.Z)