The Jenner is one of the rare BattleMechs first designed during the Succession Wars, first constructed in 2784 by Diplan Mechyards on Ozawa, under contract to House Kurita. It was designed as a fast, hit-and-run guerilla fighter. With a maximum speed of 118.8 kilometers per hour and a jump capacity of 150 meters, it was hoped that this 'Mech would form the foundation for a new, highly mobile lance.
       The original Jenners mounted two Agra 27C medium lasers and a Diplan HD large laser on a central turret, but this configuration could easily be disarmed by a direct hit to the turret. The medium lasers' targeting system was also plagued with problems. However, because the chassis and mobility sub-systems performed well in trials, designers decided to refit the weapons systems instead of scrapping the whole design. Numerous variants have seen battle in the centuries since, the last major one being ordered by Coordinator Ricol after his ascension to the throne.

         Luthien Armor Works based the JR7-R off the F variant, what they considered the most effective Jenner ever made, though they made some modifications to it. Among the fastest 'Mechs around, the Jenner packs four Argra 3L medium lasers, good firepower at close range. Its optimum range is 30 to 90 meters, and its speed and jump capability make it hard to hit. The Jenner can move in quickly, make its attack, and retreat before it can be seriously damaged. Because the Argra 3L medium lasers are the Jenner's main armament, the 'Mech can operate for long periods without running out of ammunition.
         The Shigunga unguided missile launcher was added at the behest of the new Coordinator, some say to placate Shigunga Enterprises, and some say to placate the MechWarriors that think the Jenner should have a missile rack. It is often used as an opening salvo while the Jenner is closing, and a lance of Jenners targeting one enemy can cause heavy damage, but they must finish it with medium lasers. The addition cost the 'Mech a half ton of armor, a cost that some believe is not worth the one-time salvo.
       Although the Jenner was designed as a close-range fighter, it lacks arms for punching and other physical attacks. The Jenner's designers felt that because of the 'Mech's low tonnage, it would not be able to make efficient physical attacks. The Jenner has done well without them, except in grab-and-run raids made on enemy supply depots. During these, it lays down covering fire to allow 'Mechs with hands to gather what they can.

         The Jenner is the primary light BattleMech of the Draconis Combine, and is used to flank most major BattleMech formations. They can be found on every world of the Draconis Combine, as well as on many non-aligned worlds surrounding it.