  We fit the spectral energy distributions (SEDs) of 46 GeV - TeV BL Lac
objects in the frame of leptonic one-zone synchrotron self-Compton (SSC) model
and investigate the physical properties of these objects. We use the Markov
Chain Monte Carlo (MCMC) method to obtain the basic parameters, such as
magnetic field (B), the break energy of the relativistic electron distribution
($\gamma'_{\rm{b}}$) and the electron energy spectral index. Based on the
modeling results, we support the following scenarios on GeV-TeV BL Lac objects:
(1) Some sources have large Doppler factors, implying other radiation mechanism
should be considered. (2) Comparing with FSRQs, GeV-TeV BL Lac objects have
weaker magnetic field and larger Doppler factor, which cause the ineffective
cooling and shift the SEDs to higher bands. Their jet powers are around
$4.0\times 10^{45}~\rm{ erg\cdot s}^{-1}$, comparing with radiation power,
$5.0\times 10^{42}~\rm{ erg\cdot s}^{-1}$, indicating that only a small
fraction of jet power is transformed into the emission power. (3) For some BL
Lacs with large Doppler factors, their jet components could have two
substructures, e.g., the fast core and the slow sheath. For most GeV-TeV BL
Lacs, Kelvin-Helmholtz instabilities are suppressed by their higher magnetic
fields, leading few micro-variability or intro-day variability in the optical
bands. (4) Combined with a sample of FSRQs, an anti-correlation between the
peak luminosity $L_{\rm {pk}}$ and the peak frequency $\nu_{\rm {pk}}$ is
obtained, favoring the blazar sequence scenario. In addition, an
anti-correlation between the jet power $P_{\rm {jet}}$ and the break Lorentz
factor $\gamma_{\rm {b}}$ also supports the blazar sequence.
