The Steyr-Daimler-Puch 4K 7FA G 127 is an up-armoured version of the earlier Saurer 4K 4FA armoured personnel carrier, which was developed to meet the requirements of the Austrian Army. The APC is fitted with the Steyr-Daimler-Puch 7FA diesel engine and transmission installed in the SK 105 tank destroyer, which was also manufactured by Steyr-Daimler-Puch. The first prototype of the 4K 7FA G 127 was completed in 1976, with first production vehicles following in 1977. The Steyr-Daimler-Puch 4K 7FA G 127 has been exported to Bolivia (6), Greece (manufactured under licence) and Nigeria (170).

There have been no recent sales of this vehicle and Steyr-Daimler-Puch is now concentrating on marketing the ASCOD infantry combat vehicle that it has developed in association with the now General Dynamics Santa Bárbara Sistemas of Spain. In Spanish Army service this is called the Pizarro and in Austrian Army service the Ulan. The latter is built to a higher standard. The Austrian Army has taken delivery of a total of 112 Ulan vehicles. This number is not sufficient to replace the older Saurer 4K 4FA vehicles of the Austrian Army.

The basic model is designated the 4K 7FA G 127 and is armed with a .50 (12.7 mm) M2 HB Browning machine gun. The hull is made of all-welded steel and is immune to penetration from 20 mm armour-piercing projectiles over its frontal arc.

The driver sits at the front of the hull on the left side with the engine on the right. They have a two-piece hatch cover that opens to the left and right, in front of which are three day periscopes. The centre periscope can be replaced by a passive periscope for driving at night.

The gunner sits behind the driver and has a cupola with a two-piece hatch cover opening left and right which can be locked vertical to give some protection. There are two day observation periscopes in the front part of the cupola. A standard .50 (12.7 mm) Browning M2 machine gun is mounted on the forward part of the cupola and mounted on the rear are four smoke grenade dischargers which point to the rear of the vehicle. When unlocked, the .50 (12.7 mm) machine gun has an elevation from -20 to +35° and when locked -10 to +7.5°.

The personnel compartment is at the rear of the hull with the eight infantrymen seated on bench seats, four down each side of the troop compartment at the rear facing inwards.

The section leader, the first person on the right bench, is provided with a day periscope in the forward part of the personnel compartment, on the right side. Two hatches over the roof of the vehicle open outwards. Mounting sockets for the pivot trunnion of an adaptor mount for the MG 74 machine guns are provided on the front, right, left and rear side of the hatch, above the personnel compartment. Normal means of entry and exit for the crew is by the twin doors at the rear of the hull.

The torsion bar suspension either side has five dual road wheels with the drive sprocket at the front, idler at the rear and three track-return rollers. The first and last road wheel stations are provided with a hydraulic shock-absorber. The end-connector tracks are provided with rubber pads and can be fitted with spikes for operation on icy surfaces.

Standard equipment includes a ventilation system for the crew compartment and a vehicle heater, while optional equipment includes a passive night vision device for the driver, an automatic fire extinguishing system for the engine compartment, an automatic fire suppression system for the crew compartment, a collective NBC system and an air conditioning system.

The 4K 7FA G 127 APC shares a number of common sub-systems with the SK 105 tank destroyer. Based on the latest, the company has a command post vehicle which has been exported to Botswana.

Steyr-Daimler-Puch developed an upgrade package for its 4K 7FA G 127 armoured personnel carrier along similar lines to that offered for its SK 105 tank destroyer.

This includes the installation of a ZF 6HP 600 fully automatic transmission with torque converter and lock-up clutch, improved air cooling system, cyclone-type air filter system and driver's image intensification night viewer.

Other modifications include hydraulic bump stops for improved cross-country mobility, 250 Ah dry batteries and a fire detection and suppression system.

For desert operations the 4K 7FA G 127 can be fitted with sand shields, an improved cooling system and a cyclone-type air cleaner.

This model carries a total of 10 people: section leader/commander, driver, machine gunner and seven infantrymen. The driver is front left as normal with the section leader seated at the front right corner of the crew compartment on a hinged single seat. The section leader is provided with a rotatable day periscope that can be traversed through 360°.

The vehicle is fitted with four ball mountings with day periscopes above and the former allow for insertion of a Steyr 5.56 mm calibre AUG 508 assault rifle or a Steyr MP81 sub-machine gun, two either side of the rear fighting compartment. There are also two day periscopes in the hull rear.

Four of the seven infantrymen sit back-to-back down the centre of the vehicle so that they can use the ball-mounted weapons. The remaining members of the infantry section are seated on hinged single seats, one at each remaining corner of the fighting compartment.

Two hatches over the hull roof open outwards. Mounting sockets for the pivot trunnion of an adaptor mount for the 7.62 mm MG of the infantry section are provided on the front, right, left and rear sides of the hatch.

This is the basic G 127 with a modified hull that can be fitted with various 90 mm turrets including the French Nexter Systems TS 90 or CMI Defence LCST 90 turret system already manufactured for Kuwait, Qatar and Saudi Arabia. This model is not yet in production.

This model has a crew of seven: commander, gunner, two radio operators, two messengers and the driver. Communications equipment includes two radios with an automatic tuning unit, a loudspeaker and a crew intercom.

Its crew of two consists of the driver and a medical orderly. It can carry up to four sitting and two stretcher patients and carries extensive medical equipment.

Mortar carrier with a crew of five (driver, commander, gunner and two mortar operators) armed with an 81 mm mortar and carrying 78 mortar bombs.