The Interstate 31M-AGM is a 12V Group 31M pure-lead AGM battery for boats and RVs — a 2-in-1 design with the cranking power to start an engine and the deep-cycle reserve to run electronics and accessories. Sealed and spill-proof.
Specifications
| Group Size | 31M |
|---|---|
| Voltage | 12V |
| Technology | Pure lead AGM (sealed, spill-proof) |
| Type | Dual purpose — starting + deep cycle |
| Cold Cranking Amps (CCA) | 925 |
| Reserve Capacity | 200 minutes |
| Capacity | 100 Ah |
| Terminals | Dual — SAE top posts + threaded studs |
| Dimensions | 13" L × 6 13/16" W × 9 7/16" H |
| Warranty | 36 months |
Will it fit?
Boats and RVs that use a Group 31 / 31M battery. Check the terminal style on your current battery, or call (650) 583-6735 and we'll confirm the fit.
Not sure? Use the Battery Finder with your year, make and model, match the group number on your current battery, or call (650) 583-6735.
What you get at Peninsula Battery
- Free battery testing — make sure it’s really the battery before you buy
- Ready in about 1 hour for pickup at our South San Francisco shop
- Same-day local delivery — $35 within 25 miles when you order by 1 pm (Mon–Fri); after 1 pm, next business day
- Installation available at our shop
- Old battery recycling and core exchange (a refundable core deposit may apply)
Why Peninsula Battery?
Locally owned and serving the Bay Area since 1993. Trusted by Bay Area fleets, airlines, healthcare systems and government agencies. DBE and ACDBE certified. Visit us at 1139 Airport Blvd, South San Francisco, or call (650) 583-6735 (Mon–Fri, 8:00 am–4:30 pm).