A photo can be seen in Jane's Infantry Weapons: 1988-89 on page 71.
AboutThis model was designed to fire through a "loop hole" or armored vehicle port. The barrel is extended with a fitted locking collar for port-mounting. A special scope mount is also attached with an AUG optical sight.
Exact barrel length unknown.
References
Hogg, Ian V. (1988). Jane's Infantry Weapons: 1988-89 (Fourteenth Edition). Jane's Information Group, P.71. | ISBN 0-7106-0857-8