# Car battery Optima RTC-4.2 12V 50Ah 815A AGM

![Car battery Optima RTC-4.2 12V 50Ah 815A AGM](https://baterias.com/3812-home_default/battery-optima-red-top-rtc-42-8001-287-12v-50ah.jpg)

> Optima RTC-4.2 car battery 12V 50Ah 815A AGM. RED TOP range. Dimensions 254×175×200 mm. Check fitment by plate.

**Category:** [Car Batteries](https://baterias.com/gb/car-batteries) → [OPTIMA](https://baterias.com/gb/optima)

- **Canonical URL**: https://baterias.com/gb/battery-optima-red-top-rtc-42-8001-287-12v-50ah
- **Language**: en-GB
- **Brand**: OPTIMA
- **Reference**: BCOM-OPTIMA-RTC-4.2
- **EAN**: 4016987113455
- **MPN**: RTC-4.2
- **Price**: 185,80 €
- **Stock**: In stock

## Technical specifications

| Feature | Value |
|---|---|
| Brand | OPTIMA |
| Reference | RTC-4.2 |
| Model | OPTIMA RED TOP |
| Voltage (V) | 12 V |
| Largo | 254 mm |
| Ancho | 172 mm |
| Alto | 184 mm |
| Peso | 18 kg |
| Tecnología | AGM ESPIRAL |
| EAN | 4016987113455 |
| Terminal layout | 8 |
| Terminal type | 1 |
| Cold cranking amps (EN) | 815 A |
| Capacity (C20) | 50 Ah (c20) |
| ETN | 8012870008882 |

## Quick description

**Optima RTC-4.2 12V 50Ah 815A** is a starter battery with OEM-equivalent quality, designed for modern passenger cars. Delivers reliable cold-cranks even after weeks of inactivity and supports stable auxiliary loads (lights, climate control, infotainment).

## Why this car battery?

- **Original-equipment quality** without dealership prices
- **Lasts 4 to 6 years** buy once instead of twice
- **Real human tech support** if you have any doubts before buying

🔌 Voltage
12 V

⚡ Capacity
50 Ah C20

🔋 Cold cranking
815 A EN-1

📏 Dimensions
254×175×200 mm

⚙️ Technology
AGM ESPIRAL

⚖️ Weight
18,5 kg

🏷️ Model
OPTIMA RED TOP

## Description

## Car battery Optima RTC-4.2 Red Top 50Ah 815A 12V

12*V* Voltage
50*Ah* Capacity
815*A* Cold cranking
18*kg* Weight

The **Optima RTC-4.2 car battery** is rated at **12 V**, **50 Ah** and **815 A** of cold cranking current (EN) from the **Red Top** range, and is designed for passenger cars with conventional starting, without a Start-Stop system. It measures 254 × 172 × 184 mm, the format sought by anyone replacing a 50 Ah battery in cars.
- Reliable cold starts, even after weeks without driving.
- Spiral cells: maximum vibration resistance and very powerful cranking.
- Original-equipment build quality without the dealership price.
- Direct replacement for the original battery in size and terminals.

### Vehicles compatible with the Optima RTC-4.2

The Optima RTC-4.2 is compatible with more than 14 vehicles: it is fitted as original equipment or as a replacement by brands such as Jeep, Chrysler, Fiat, Dodge and New Holland. It is a go-to option when you need a **battery for a Jeep**, Chrysler or other models that use this same format.

### The Optima RTC-4.2: Red Top range and spiral-cell AGM technology

Within the Optima catalogue, the **Red Top** series groups the references designed for this use. The RTC-4.2 is the 50 Ah model of that family, with the same performance as its siblings in other sizes.
Spiral AGM construction winds the plates into cylindrical pure-lead cells: maximum active surface, extreme vibration resistance and cranking current far above a battery of the same size.

### Will it fit your current battery tray?

The Optima RTC-4.2 is made in the 254 × 172 × 184 mm format and weighs 18 kg. It uses 1 terminals, the system that anchors and connects it in the vehicle. Checking the three dimensions and the terminal position before buying avoids the most common mistake when replacing a battery.

### Why choose Optima batteries

Optima makes spiral-cell (SpiralCell) AGM batteries with pure lead: maximum vibration resistance, very powerful cranking and a durability recognised in 4x4, motorsport, marine and car audio. At baterias.com we work directly with the manufacturer or its official distributor: real stock, brand-new product and official warranty.

### How to make it last longer

Keep the terminals clean and tight, and check that the resting voltage does not drop below 12.4 V: below that it is time to recharge. In normal daily use the alternator keeps the battery charged; if the car stands for weeks, a maintenance charge once a month prevents deep discharge.

### Manufacturer's warranty

The Optima RTC-4.2 comes with the **manufacturer's official warranty** against manufacturing defects; the exact period is stated in the brand's conditions. If it fails through a defect within the period, we replace it free of charge.

### When you get it and how to return it

Same-day dispatch from our warehouse for in-stock orders placed **before [[ks:cutoff]]**: 24-48 working hours in mainland Spain and Portugal, 3 to 5 days in the islands and the rest of Europe. Returns are accepted for **[[ks:return_days]] days** if the battery has not been used (free collection on the Iberian mainland). You will receive tracking by email.

## Frequently asked questions

### Is the Optima RTC-4.2 an AGM battery and what are the benefits of AGM?

Yes. The RTC-4.2 from Optima uses AGM (Absorbent Glass Mat) technology: a sealed lead-acid battery where the electrolyte is absorbed in a glass-fibre mat. It withstands more charge/discharge cycles than a conventional one, handles heat better and is the required technology for cars with advanced Start-Stop and regenerative braking. Expected lifespan: 5-8 years under normal conditions.

### Is the Optima RTC-4.2 battery suitable for Start-Stop?

Yes. As AGM technology it is designed for Start-Stop vehicles. AGM batteries support advanced Start-Stop and regenerative braking thanks to their higher cycle count. EFB is recommended for basic Start-Stop; AGM is recommended when regenerative braking is also present, thanks to its higher cycle capability. It works straight out of the box — on most modern vehicles registering the battery via OBD is recommended so the alternator automatically applies the optimal charging profile.

### How is the Optima RTC-4.2 battery installed in the vehicle?

In most cars it fits in 15-30 minutes with a 10 mm wrench; if the battery is under the seat or in the boot the time can double. See the step-by-step guide on our blog. Quick summary: 1) switch off the engine and remove the key; 2) locate the original battery (engine bay, boot or under seat); 3) disconnect the negative (−) terminal first, then the positive (+); 4) loosen the hold-down clamp and remove the old battery; 5) fit the new one in the same orientation — match the polarity shown on the product sheet; 6) connect the positive (+) first, then the negative (−). On cars with Start-Stop or BMS, register the battery via OBD so the alternator applies the correct charging profile.

### How long does the Optima RTC-4.2 battery last?

Expected lifespan of the Optima RTC-4.2 is 5 to 8 years in mild-climate car use with Start-Stop. In cold regions it drops slightly due to cold-start stress; in very hot regions it also drops because of electrolyte evaporation. To extend its life: avoid deep discharges (headlights on with engine off), have the alternator checked yearly, and keep the battery clean and properly secured.

### What are the dimensions of the Optima RTC-4.2 battery?

Dimensions (length × width × height) are 254×175×200 mm — also written as 254x175x200 mm — following the European DIN standard. Always measure the space in your car before buying: even one extra millimetre can prevent the hold-down clamp from closing. The height shown includes the terminals.

### What ETN and EAN codes does the Optima RTC-4.2 battery have?

The manufacturer reference (MPN) is RTC-4.2 and its ETN code is 8012870008882 (short form 801 287 000), the European identifier used in spare-part catalogues. The EAN-13 barcode is 4016987113455. It belongs to the OPTIMA RED TOP range. Any of these codes identifies exactly this battery when requesting quotes or comparing prices.

### Is the RTC-4.2 valid for my vehicle?

Three options to confirm: 1) enter your number plate in the finder (DGT/DVLA/KBA auto-detect your model and engine); 2) check the "Compatible vehicles" tab on this page, where we list every vehicle verified by our technical team; 3) if you cannot find your model, message us on WhatsApp with brand, model, engine and year — we reply during business hours (Mon–Fri 10:00–13:30 and 16:40–18:00 (Spanish time, CET)). The RTC-4.2 fits 12 verified vehicle versions in our database.

### Which batteries are equivalent to the Optima RTC-4.2?

Directly interchangeable batteries (same dimensions, same polarity, same Ah and CCA) are the OEM equivalents from leading brands: Bosch, Tudor, Exide and, depending on the model, Banner or Yuasa. Exact equivalence depends on technology — an EFB cannot be replaced with a conventional battery in Start-Stop cars. See the "Equivalents" section to view recommended options at the same performance level.

### What advantages does the Optima RTC-4.2 AGM battery offer over an EFB?

AGM (Absorbent Glass Mat) technology uses absorbent fibreglass that retains the electrolyte, eliminating leaks and allowing up to 3× more charge/discharge cycles than a conventional battery. It is the recommended option when the car has advanced Start-Stop with regenerative braking (BMW EfficientDynamics, Mercedes Eco, Audi MHEV, Land Rover ECO, Volvo i-Stop). Withstands tilted positions, high vibration and extreme temperatures better than EFB. The Optima RTC-4.2 is fully original and meets European EN 50342-6 standards for advanced Start-Stop.

### Do I need to register the Optima RTC-4.2 on the car after installation?

On most cars it is not strictly necessary — the alternator detects the new battery and adapts the charge automatically. It is recommended to register the battery via OBD so that the alternator applies the optimal charging profile from the first minute and extends the battery life as much as possible (especially on brands with sophisticated BMS: BMW, Mercedes, Audi, Volvo, Land Rover). Any workshop with an OBD scanner (~10-15 € labour) does it in 5 minutes. DIY apps: VCDS / Carista (VAG), Bimmercode (BMW), iCarsoft. If you do not register, the car will still start correctly — the alternator just takes a few days to adjust the profile. The Optima RTC-4.2 ships factory-charged at 80-90% so you can use it straight after fitting.


## Compatible vehicles

This battery fits 12 vehicles. Most searched:

- [JEEP RENEGADE SUV (BU, B1, BV) (2014)](https://baterias.com/gb/car-batteries/jeep/renegade-suv-bu-b1-bv)
- [JEEP CHEROKEE (KL) (2013)](https://baterias.com/gb/car-batteries/jeep/cherokee-kl)
- [FIAT FREEMONT (345\_) (2011)](https://baterias.com/gb/car-batteries/fiat/freemont-345)
- [CHRYSLER GRAND VOYAGER V (RT) (2007)](https://baterias.com/gb/car-batteries/chrysler/grand-voyager-v-rt)
- [CHRYSLER 300C (LX) (2010)](https://baterias.com/gb/car-batteries/chrysler/300c-lx)
- [DODGE JOURNEY (2008)](https://baterias.com/gb/car-batteries/dodge/journey)
- [CHRYSLER PT CRUISER (PT\_) (2000)](https://baterias.com/gb/car-batteries/chrysler/pt-cruiser-pt)
- [DODGE CALIBER (2006)](https://baterias.com/gb/car-batteries/dodge/caliber)
- [JEEP PATRIOT (MK74) (2007)](https://baterias.com/gb/car-batteries/jeep/patriot-mk74)
- [NEW HOLLAND Series BOOMER (1990)](https://baterias.com/gb/batteries-for-construction-and-agricultural-machinery/new-holland/series-boomer)
- [NEW HOLLAND Series T4 POWERSTAR (1990)](https://baterias.com/gb/batteries-for-construction-and-agricultural-machinery/new-holland/series-t4-powerstar)

## Reviews

- **Average rating**: 5 / 5 (3 reviews)

## Technical team (editorial authorship)

The FAQs, guides and comparisons on this site are reviewed by the baterias.com technical team — automotive battery specialists since 2012.

→ https://baterias.com/gb/technical-team

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*baterias.com — Automotive batteries · 2026-10-23*