# Fulmen FF1251 · Truck battery 12V 125Ah 850A

![Fulmen FF1251 · Truck battery 12V 125Ah 850A](https://bateriasonline.es/2711-home_default/fulmen-ff1251.jpg)

> Fulmen FF1251: 125 Ah truck battery, 850 A (EN), 349×175×285 mm, positive terminal on the left. Equivalent to Exide EF1251 and Tudor TF1251.

**Category:** [Truck, commercial and agricultural vehicle batteries](https://bateriasonline.es/en/truck-agricultural-batteries) → [Fulmen](https://bateriasonline.es/en/fulmen-batteries)

- **Canonical URL**: https://bateriasonline.es/en/fulmen-ff1251
- **Language**: en
- **Brand**: Fulmen
- **Reference**: BOL-FULMEN-FF1251
- **EAN**: 3661024047456
- **MPN**: FF1251
- **Last updated**: 2026-10-27

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Fulmen |
| Range | FULMEN Power Pro (HDX) |
| Application | Trucks and commercial vehicles |
| Technology | Lead-acid |
| Voltage | 12 V |
| Capacity | 125 Ah |
| Cold cranking amps (EN) | 850 A |
| Length | 349 mm |
| Width | 175 mm |
| Height | 285 mm |
| Weight | 31 kg |
| Polarity | Positive terminal on the left |

## Quick description

The Fulmen FF1251 is a truck battery with 12 V, 125 Ah and 850 A cold cranking current, measuring 349 × 175 × 285 mm, with the positive terminal on the left. If yours has the positive terminal on the right, you need the Fulmen FF1250.

## Description

## Who the Fulmen FF1251 is for

The Fulmen FF1251 is a starter battery for trucks, tractors and machinery: high capacity, robust terminals and a build that withstands vibration and the starts of large engines. With 125 Ah, the FF1251 suits heavy vehicles that had a battery of that capacity.
The FF1251 belongs to the Fulmen FULMEN Power Pro (HDX) range. [The full range of Fulmen batteries](https://bateriasonline.es/en/fulmen-batteries)

## Lead-acid technology in the FF1251

The FF1251 is a conventional lead-acid battery, with plates immersed in liquid electrolyte. In cars without energy management, the FF1251 needs no special registration: just connect it.

## Fulmen FF1251 vs FG1251, FF1250 and FG1101: which one to choose?

Torn between the FF1251 and another similar Fulmen? This is what changes:

| Model | Capacity | Cold cranking (EN) | Dimensions (mm) | Positive | Weight |
|---|---|---|---|---|---|
| Fulmen FF1251 (this one) | 125 Ah | 850 A | 349 × 175 × 285 | left | 31 kg |
| Fulmen FG1251 | 125 Ah | 760 A | 349 × 175 × 285 | left | 29.5 kg |
| Fulmen FF1250 | 125 Ah | 850 A | 349 × 175 × 285 | right | 31 kg |
| Fulmen FG1101 | 110 Ah | 750 A | 349 × 175 × 235 | left | 25.4 kg |

- Fulmen FG1251: the same capacity, 90 A less cranking power, the same dimensions.
- If the positive terminal of your battery is on the other side, the one you need is the Fulmen FF1250 (positive terminal on the right).
- Fulmen FG1101: 15 Ah less, 100 A less cranking power, a different case (349 × 175 × 235 mm).

## Equivalents and alternatives to the Fulmen FF1251

Same dimensions and polarity as the FF1251, with similar capacity and cranking power; as a conventional battery, the FF1251 can also be replaced by an EFB or AGM of the same size if you want more cycles.

| Model | Technology | Capacity | Cold cranking (EN) | Dimensions (mm) |
|---|---|---|---|---|
| Exide EF1251 | Lead-acid | 125 Ah | 850 A | 349 × 175 × 285 |
| Tudor TF1251 | Lead-acid | 125 Ah | 850 A | 349 × 175 × 285 |
| Deta DF1251 | Lead-acid | 125 Ah | 850 A | 349 × 175 × 285 |

## Fulmen FF1251 codes and part numbers

Look for any of these FF1251 codes on your current battery or in the manufacturer's catalogue:

| Commercial reference | FF1251 |
|---|---|
| EAN | 3661024047456 |
| Not to be confused with | Fulmen FF1250 (125 Ah, 850 A, positive terminal on the right), Fulmen FG1251 (125 Ah, 760 A) |

## Check this before ordering the Fulmen FF1251

- Cold cranking: 850 A (EN), equal to or higher than the original.
- Capacity of the FF1251: 125 Ah; the same as your current battery or slightly more is fine.
- Polarity of the FF1251: positive terminal on the left (if yours has it on the other side, the cables will not reach).
- Length, width and height of the FF1251: 349 × 175 × 285 mm.

## Frequently asked questions about the Fulmen FF1251

### Fulmen FF1251 or FG1251?

Compared with the FF1251, the Fulmen FG1251 has 90 A less cranking power. The FF1251 cranks harder; the FG1251 is only a good option if your original battery says 760 A or less. Both measure 349 × 175 × 285 mm, so they fit the same tray.

### What is the difference between the Fulmen FF1251 and the FF1250?

They are the same battery with the terminals swapped: positive terminal on the left on the FF1251, positive terminal on the right on the FF1250. Look at your current battery with the terminals facing you and pick the one that matches.

### How much does the Fulmen FF1251 weigh?

The FF1251 weighs 31 kg. For reference, the Fulmen FG1251 (125 Ah) weighs 29.5 kg.

### Which battery is equivalent to the Fulmen FF1251?

With the same dimensions, polarity and similar capacity you have the Exide EF1251, Tudor TF1251 and Deta DF1251. As the FF1251 is a conventional battery, an EFB or AGM of the same size also works.

## More batteries to compare with the FF1251

- [More truck, commercial and agricultural vehicle batteries](https://bateriasonline.es/en/truck-agricultural-batteries)
- [The whole Fulmen range](https://bateriasonline.es/en/fulmen-batteries)
- [Exide EF1251](https://bateriasonline.es/en/exide-ef1251) · 125 Ah, 850 A, 349×175×285 mm
- [Tudor TF1251](https://bateriasonline.es/en/tudor-tf1251) · 125 Ah, 850 A, 349×175×285 mm

---
*bateriasonline.es — Batteries and accessories · 2026-11-10*