These are lipo batteries wired with JST SH 1 mm or 1.5 mm connectors (you can request either) and intended for use with electronic DT timers and other lightweight applications (30, 40 mah batteries good for band burner timers). I use the 110 and 120 mAh batteries to run my F1G timers. The standard battery cable is 50 mm long but you can purchase a modification to get me to change the cable length and/or remove the voltage regulator to get the battery down to minimum weight. Removing the voltage regulator also ensures that the battery will work to the death (giving you that last possible DT instead of shutting down mid flight if you forget to charge it). The downside is that this will likely kill the battery requiring a replacement.