  The mass and total kinetic energy distributions of the fission fragments in
the fission of even-even isotopes of superheavy elements from Hs (Z=108) to Og
(Z=118) are estimated using a pre-scission point model. We restrict to nuclei
for which spontaneous fission has been experimentally observed. The potential
energy surfaces are calculated with Strutinsky's shell correction procedure.
The parametrization of the nuclear shapes is based on Cassini ovals. For the
just before scission configuration we fix $\alpha$=0.98, what corresponds to
$r_{neck}\approx 2$ fm, and take into account another four deformation
parameters: $\alpha_1,\alpha_3,\alpha_4,\alpha_6$. The fragment-mass
distributions are estimated supposing they are due to thermal fluctuations in
the mass asymmetry degree of freedom just before scission. The influence of the
excitation energy of the fissioning system on these distributions is studied.
The distributions of the total kinetic energy (TKE) of the fragments are also
calculated (in the point-charge approximation). In Hs, Ds and Cn isotopes a
transition from symmetric to asymmetric fission is predicted with increasing
neutron number N (at N$\approx$168). Super-symmetric fission ocurs at
N$\approx$160. When the excitation energy increases from 0 to 30 MeV, the peaks
(one or two) of the mass distributions become only slightly wider. The first
two moments of the TKE distributions are displayed as a function of the mass
number A of the fissioning nucleus. A slow decrease of the average energy and a
minimum of the width (at N$\approx$162) is found.

Nuclear Theory