The GCT 155mm is a modern self-propelled artillery vehicle currently in use by the armies of France and Saudi Arabia. It replaced the former Mk F3 155mm in French Army service. The GCT 155mm's primary advancement is that it incorporates and provides full armor and nuclear-biological-chemical (NBC) protection for its crew of four, while the former Mk F3 155mm offered no protection and could carry only two of its four crew members. Though 60% heavier than the American M109, the GCT 155mm is both faster, and incorporates a more sophisticated fire control system[citation needed]. The GCT 155mm saw combat with the Iraqi Army in the Iran–Iraq War.