Question: Hi, I have the following code accessing a URL:

```
NSString * stringURL = [NSString stringWithFormat:@"%@/%@/someAPI", kSERVICE_URL, kSERVICE_VERSION];
NSURLRequest * request = [NSURLRequest requestWithURL:[NSURL URLWithString:stringURL]];

AFJSONRequestOperation * operation = [AFJSONRequestOperation JSONRequestOperationWithRequest:request success:^(NSURLRequest *request, NSHTTPURLResponse *response, id JSON) {
    completionHandler(JSON, nil);
} failure:^(NSURLRequest *request, NSHTTPURLResponse *response, NSError *error, id JSON) {
    completionHandler(nil, error);
}];

```

But I want to pass the user token as a parameter on `HEADER`, like `X-USER-TOKEN`.

Cant find it on `AFNetworking documentation`, should I change the operation type?

Answer: 
```
NSMutableURLRequest* request = [[NSMutableURLRequest alloc] initWithURL:url];

[request setValue: @"X-USER-TOKEN"  forHTTPHeaderField:@"< clientToken >"];

[AFJSONRequestOperation JSONRequestOperationWithRequest: request ...]

```
If you have a layer of abstraction, let's say APIManager,
then you should do the following inside a particular method

```
 [[HTTPClient sharedHTTPClient].requestSerializer setValue:YOUR_KEY forHTTPHeaderField:@"X-Register"];

```