A 4π multi-dectector array for measuring the charged particles in intermediate energy heavy ion induced reactions is described. It consists of 276 detector telescope units

each unit is composed of fast and slow plastic scintillator phoswiches

or fast plastic scintillator and CsI(TI) phoswiches or silicon detector telescopes. The array covers geometrically 85%-90% of the 4 π solid angle with low detection thresholds. The detecotrs

operated under vacuum

are axially symmetrically arranged around the beam line. 1

2

3H

3

4He isotopes and elements from Li to Ar can be identified and their energies can be measured over a large dynamic range.