  AH Cep and CW Cep are both early B-type binaries with short orbital periods
of 1.8~d and 2.7~d, respectively. All four components are B0.5V types. The
binaries are also double-lined spectroscopic and eclipsing. Consequently,
solutions for orbital and stellar parameters make the pair of binaries ideal
targets for a study of the colliding winds between two B~stars. {\em Chandra}
ACIS-I observations were obtained to determine X-ray luminosities. AH~Cep was
detected with an unabsorbed X-ray luminosity at a 90\% confidence interval of
$(9-33)\times 10^{30}$ erg s$^{-1}$, or $(0.5-1.7)\times 10^{-7} L_{\rm Bol}$,
relative to the combined Bolometric luminosities of the two components. While
formally consistent with expectations for embedded wind shocks, or binary wind
collision, the near-twin system of CW~Cep was a surprising non-detection. For
CW~Cep, an upper limit was determined with $L_X/L_{\rm Bol} < 10^{-8}$, again
for the combined components. One difference between these two systems is that
AH~Cep is part of a multiple system. The X-rays from AH~Cep may not arise from
standard wind shocks nor wind collision, but perhaps instead from magnetism in
any one of the four components of the system. The possibility could be tested
by searching for cyclic X-ray variability in AH~Cep on the short orbital period
of the inner B~stars.
