# Car constants

This endpoint returns localised car rental constants used across the Cars API collection, such as extras, fuel policies, payment timings, and transmission types.

It also returns customer service contact email addresses per requested language for partner support scenarios where Booking.com handles travellers communication directly. 
To retrieve the full list, make the request with an empty body.

Endpoint: POST /cars/constants
Version: 3.2
Security: BearerAuth

## Header parameters:

  - `X-Affiliate-Id` (integer, required)
    Include here your Affiliate identifier number

## Request fields (application/json):

  - `constants` (array)
    Use this field to limit the response to specific categories, such as fuel_policies, depot_services, customer_services, etc. If omitted, all constant groups are returned.
    Enum: "customer_services", "depot_services", "extras", "special_offers", "fuel_policies", "fuel_types", "general", "payment_timings", "transmission"

  - `languages` (array)
    List of language codes used to localise constant names. Each constant name is returned as a translated object keyed by language. If not provided, en-gb is used by default.
    Example: ["en-us"]

## Response 200 fields (application/json):

  - `request_id` (string)
    Uniquely identifies the request. Please provide this identifier when contacting support.

  - `data` (object)
    Contains constant groups keyed by constant type. Each group includes a list of constant identifiers and their translated names.

  - `data.customer_services` (array)
    Customer service contact details per language. For each requested language, the API returns the appropriate customer support email address. English uses the default address, while other languages use a language-specific suffix.

  - `data.customer_services.id` (string)

  - `data.customer_services.name` (object)
    A string localised in multiple languages.

  - `data.customer_services.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.depot_services` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.depot_services.id` (string)

  - `data.depot_services.name` (object)
    A string localised in multiple languages.

  - `data.depot_services.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.extras` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.extras.id` (string)

  - `data.extras.name` (object)
    A string localised in multiple languages.

  - `data.extras.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.special_offers` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.special_offers.id` (string)

  - `data.special_offers.name` (object)
    A string localised in multiple languages.

  - `data.special_offers.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.fuel_policies` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.fuel_policies.id` (string)

  - `data.fuel_policies.name` (object)
    A string localised in multiple languages.

  - `data.fuel_policies.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.fuel_types` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.fuel_types.id` (string)

  - `data.fuel_types.name` (object)
    A string localised in multiple languages.

  - `data.fuel_types.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.general` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.general.id` (string)

  - `data.general.name` (object)
    A string localised in multiple languages.

  - `data.general.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.payment_timings` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.payment_timings.id` (string)

  - `data.payment_timings.name` (object)
    A string localised in multiple languages.

  - `data.payment_timings.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.

  - `data.transmission` (array)
    Represents a constant identifier and its translated display names for the requested languages.

  - `data.transmission.id` (string)

  - `data.transmission.name` (object)
    A string localised in multiple languages.

  - `data.transmission.name.^[a-z]{2}(-[a-z]{2})$` (string,null)
    The content localised in this language.