[Home](./index.md) > [sip.js](./sip.js.md) > [Registerer](./sip.js.registerer.md) ## Registerer class A registerer registers a contact for an address of record (outgoing REGISTER). Signature: ```typescript export declare class Registerer ``` ## Constructors | Constructor | Modifiers | Description | | --- | --- | --- | | [(constructor)(userAgent, options)](./sip.js.registerer._constructor_.md) | | Constructs a new instance of the Registerer class. | ## Properties | Property | Modifiers | Type | Description | | --- | --- | --- | --- | | [contacts](./sip.js.registerer.contacts.md) | | Array<string> | The registered contacts. | | [state](./sip.js.registerer.state.md) | | RegistererState | The registration state. | | [stateChange](./sip.js.registerer.statechange.md) | | Emitter<RegistererState> | Emits when the registerer state changes. | ## Methods | Method | Modifiers | Description | | --- | --- | --- | | [dispose()](./sip.js.registerer.dispose.md) | | Destructor. | | [register(options)](./sip.js.registerer.register.md) | | Sends the REGISTER request. | | [unregister(options)](./sip.js.registerer.unregister.md) | | Sends the REGISTER request with expires equal to zero. Rejects with RequestPendingError if a REGISTER request is already in progress. |