The XT-69 155 mm self-propelled extended range gun was developed by the Combined Service Forces and is identical in layout and concept to the basic XT-69.

It is fitted with a 155 mm/45 calibre weapon which may have been developed from a foreign imported 155 mm calibre towed artillery system.

The 155 mm/45 calibre ordnance has a multibaffle muzzle brake, a fume extractor and a travelling lock that folds back onto the glacis plate when not in use. Maximum range is said to be 30,000 m with the Extended-Range Full-Bore projectile, and over 35,000 m with a base bleed projectile. A maximum rate of fire of 6 rds/min is claimed to be achieved, due to a pneumatically assisted loading device that enables the weapon to be uniformly loaded at any angle of elevation. Elevation is estimated to be from 0 to +70° and traverse 30° left and right. The weapon is used in conjunction with a battery fire-control system developed by the Sun Yat-sen Scientific Research Institute in Taiwan.

The XT-69 system has a crew of five and is fitted with night vision equipment for the driver and a .50 (12.7 mm) M2 HB anti-aircraft machine gun. No NBC system is fitted.

The chassis is based on the US now BAE Systems, Ground Systems (previously United Defense) M108/M109 self-propelled artillery system covered in a separate entry. Production of the M109 series is undertaken on an as required basis.