# Optima YTS-4.2 · Motorhome battery 12V 55Ah 765A

![Optima YTS-4.2 · Motorhome battery 12V 55Ah 765A](https://bateriasonline.es/3892-home_default/optima-yts-4-2.jpg)

> Optima YTS-4.2 (ETN 812254000): 55 Ah motorhome battery, 765 A (EN), 254×175×200 mm, positive terminal on the left.

**Category:** [Leisure batteries for motorhomes and caravans](https://bateriasonline.es/en/leisure-batteries-motorhome-caravan) → [Optima](https://bateriasonline.es/en/optima-batteries)

- **Canonical URL**: https://bateriasonline.es/en/optima-yts-4-2
- **Language**: en
- **Brand**: Optima
- **Reference**: BOL-OPTIMA-YTS-4.2
- **EAN**: 4016987113523
- **MPN**: YTS-4.2
- **Price**: 209,20 € (VAT incl., Spain)
- **Last updated**: 2026-11-06

## Technical specifications

| Feature | Value |
|---|---|
| Brand | Optima |
| Range | OPTIMA YELLOW TOP |
| Application | Motorhomes and caravans |
| Technology | Spiral AGM |
| Voltage | 12 V |
| Capacity | 55 Ah |
| Cold cranking amps (EN) | 765 A |
| Length | 254 mm |
| Width | 175 mm |
| Height | 200 mm |
| Weight | 20.3 kg |
| Polarity | Positive terminal on the left |
| ETN code | 812254000 |

## Quick description

Optima YTS-4.2 (ETN 812 254 000, also written 812254000): motorhome battery with 12 V, 55 Ah and 765 A cold cranking current, measuring 254 × 175 × 200 mm, with the positive terminal on the left.

## Description

## The Optima YTS-4.2 at a glance

The Optima YTS-4.2 is made for the living area of a motorhome. Unlike the starter battery, it takes slow, deep discharges night after night.
The YTS-4.2 belongs to the Optima OPTIMA YELLOW TOP range. [More Optima batteries](https://bateriasonline.es/en/optima-batteries)

## Spiral AGM technology in the YTS-4.2

Inside, the YTS-4.2 rolls its plates into cylindrical cells (spiral AGM). It is the basis of OPTIMA batteries.

## Equivalents and alternatives to the Optima YTS-4.2

Other AGM batteries that fit the YTS-4.2's tray with the same polarity: an AGM can only be replaced by another AGM.

| Model | Technology | Capacity | Cold cranking (EN) | Dimensions (mm) |
|---|---|---|---|---|
| Optima YTU-4.2 | Spiral AGM | 55 Ah | 765 A | 254 × 175 × 200 |

## Part numbers and codes for the Optima YTS-4.2

This is how the Optima YTS-4.2 appears on the label and in parts catalogues:

| Commercial reference | YTS-4.2 |
|---|---|
| ETN code | 812254000 (also 812 254 000) |
| EAN | 4016987113523 |
| Case size according to Optima | 34 (BCI) |
| Base hold-down | B00 |
| Also known as | Optima 812254000 · Optima 812 254 000 |
| Not to be confused with | Optima RTS-4.2 (50 Ah, 815 A) |

## Check this before ordering the Optima YTS-4.2

- The YTS-4.2 delivers 765 A cold cranking (EN standard); do not go below what your original battery states.
- Capacity of the YTS-4.2: 55 Ah; the same as your current battery or slightly more is fine.
- The YTS-4.2 has the positive terminal on the left: compare it with your current battery.
- Length, width and height of the YTS-4.2: 254 × 175 × 200 mm.

## Frequently asked questions about the Optima YTS-4.2

### What is the ETN code of the Optima YTS-4.2?

812254000, also written 812 254 000. The ETN (European Type Number) is printed on the label and used in parts catalogues.

### How much does the Optima YTS-4.2 weigh?

20.3 kg, with 55 Ah of capacity.

### Which battery is equivalent to the Optima YTS-4.2?

Only other AGM batteries with its dimensions and polarity: Optima YTU-4.2. Neither an EFB nor a conventional battery replaces the YTS-4.2.

### What is the cold cranking current of the Optima YTS-4.2?

765 A to the EN standard, with 55 Ah capacity.

### Which side is the positive terminal on the Optima YTS-4.2?

On the YTS-4.2, the positive terminal is on the left with the terminals facing you: compare it with your current battery, because with reversed polarity the cables will not reach.

### Can it be charged from the engine and from solar panels at the same time?

Yes, with a solar regulator and a charge booster or relay from the alternator. Both sources can coexist if each has its own controller.

## Keep comparing: alternatives to the YTS-4.2

- [All leisure batteries for motorhomes and caravans](https://bateriasonline.es/en/leisure-batteries-motorhome-caravan)
- [The whole Optima range](https://bateriasonline.es/en/optima-batteries)
- [Optima YTR-5.0](https://bateriasonline.es/en/optima-ytr-5-0) · 66 Ah, 845 A, 309×172×219 mm

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