In collaboration between Rattlesnake RC and Fantom Racing Batteries we have worked together in providing these outstanding batteries. 
6300 MAH Marine Racing Series LiPo Battery
130C Hydro -X Pro Cells
14.8 Volt
Factory 8 mm Male Bullet on Negative
Factory 8 mm Female Bullet on Positive
Overall Length 154 mm
Overall Width 37 mm
Overall Height 45 mm
Soft Packs made to my specs and raced by me.
IMO you won’t find a more powerful racing pack for running 8S with 2 in Series.