Doher (galloper) was introduced to the artillery forces personnel in 1993, Doher is improved Rochev (M109A1 and M109A2). The IDF maintenance units designed it. This model was the last one on a row of designs, none of which made it to serial production. From this year, till 1997, all of the active service Rochevs were replaced by the Doher. After the active service units received their share, the IDF began to replace some of the reserve units' vehicles. Today one can find in the reserve units both the Doher & Rochev.

All types share the same hull, turret, barrel, engine & transmission. Most of the improvements of the Doher are internal and can't be seen from the outside: Inertial Navigating System (INS), air filtering system, and some changes in the driver's panel & cabin and NBC protection added. The external, visual differences are:

1. Two sub machine guns on the Doher's turret, only one in the Rochev. The additional SMG is positioned near the sight ballistic shield.

2. Electrical travel lock (known in Hebrew as "BiFoot") – in the Rochev one of the crewmen has to lock manually the barrel, most of the time the driver, with the assistance of the sight operator. In the Doher the crewmen can do it automatically, by electrical operation. The Doher's travel lock is thicker than the Rochev's, and has a rectangle box in its front side.

3. External Generator – the Doher is equipped with external Generator, positioned instead the right-back basket and its two external cells. Due to the lack of one basket, the left basket is a bit bigger (to contain the camouflage cover).

4. Different shape of the commander's turret – the Doher's NCO turret can be locked in slit position, a position that does not exist in the Rochev.

5. Different Tactical markings – the upgraded capabilities of the Doher changed in some manners the way the artillery battery is operated. Due to this fact, beside the different kind of V's and numbers, one can find also a Hebrew letter (Aleph, Beit, Gimel) markings.

Most of these were upgraded in Israel to a new standard under the local name of the Doher. According to the Israel Defence Force, the upgraded Doher has a number of significant operational advantages including:

• Shorter response time

• High mission availability

• Capability to provide a wide deployment

• Maximum flexibility in operating the artillery battery among others, by leap frogging

• High firing accuracy that results from technological improvements in the systems

• Fighting under NBC conditions and completing the mission under battery fire

• Improving the survivability of the crew by installing a number of new and more modern subsystems including automatic fire detection and suppression system, central NBC filtration system, ability to lay a smoke screen by injecting diesel fuel into the engine exhaust on the right side of the forward part of the hull, installation of another 7.62 mm or .50 (12.7 mm) M2 HB MG on the roof and passive night vision equipment for the driver and commander

The crew of seven consists of the commander, navigator, gunner, person in charge of parking and refuelling, driver and two soldiers who join the crew from the Alfa ammunition vehicle.

It is understood that all M109s in service with the Israel Defence Force are fitted with a 155 mm/39 calibre ordnance.

Minor modifications carried out to the Doher in IDF service are understood to include additional track links, improved lighting and external bars on the hull sides for additional equipment stowage.

While the Israeli defence industry does not offer completed 155 mm M109s for the export market, it can provide a number of upgrades for this system, especially in the areas of fire control and turret modernisation. Soltam Systems is the main contractor in Israel for 155 mm artillery systems and their associated ordnance.

This is a slightly modified version of the now BAE Systems, Ground Systems 175 mm M107 self-propelled gun.