In this paper, we study a proposal put forward recently by Bodendorfer, Mele
    and M\”unch and Garc\’\i{}a-Quismondo and Marug\’an, in which the two
    polymerization parameters of spherically symmetric black hole spacetimes are
    the Dirac observables of the four-dimensional Ashtekar’s variables. In this
    model, black and white hole horizons in general exist and naturally divide the
    spacetime into the external and internal regions. In the external region, the
    spacetime can be made asymptotically flat by properly choosing the dependence
    of the two polymerization parameters on the Ashtekar variables. Then, we find
    that the asymptotical behavior of the spacetime is universal, and, to the
    leading order, the curvature invariants are independent of the mass parameter
    $m$. For example, the Kretschmann scalar approaches zero as $K \simeq
    A_0r^{-4}$ asymptotically, where $A_0$ is generally a non-zero constant and
    independent of $m$, and $r$ the geometric radius of the two-spheres. In the
    internal region, all the physical quantities are finite, and the Schwarzschild
    black hole singularity is replaced by a transition surface whose radius is
    always finite and non-zero. The quantum gravitational effects are negligible
    near the black hole horizon for very massive black holes. However, the behavior
    of the spacetime across the transition surface is significantly different from
    all loop quantum black holes studied so far. In particular, the location of the
    maximum amplitude of the curvature scalars is displaced from the transition
    surface and depends on $m$, so does the maximum amplitude. In addition, the
    radius of the white hole is much smaller than that of the black hole, and its
    exact value sensitively depends on $m$, too.

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