  This paper documents package for the particle level fast simulation. The
package is designed to complete the AcerMC generator framework with the
easy-to-use simulation and reconstruction algorithms. The package provides,
starting from list of particles in the event, the list of reconstructed jets,
isolated electrons, muons and photons and reconstructed missing transverse
energy. The AcerDET represents a simplified version of the package called
ATLFAST, used since several years within ATLAS Collaboration. In the AcerDET
version some functionalities of the former one have been removed, only the most
crucial detector effects are implemented and the parametrisations are largely
simplified. Therefore it is not representing in details neither ATLAS nor CMS
detectors. Nevertheless, we believe that the package can be well adequate for
some feasibility studies of the high pT physics at LHC and in future, after
some adjustments, of other detectors as well.
