[Home](./index.md) > [sip.js](./sip.js.md) > [ClientTransaction](./sip.js.clienttransaction.md) > [(constructor)](./sip.js.clienttransaction._constructor_.md) ## ClientTransaction.(constructor) Constructs a new instance of the `ClientTransaction` class Signature: ```typescript protected constructor(_request: OutgoingRequestMessage, transport: Transport, user: ClientTransactionUser, state: TransactionState, loggerCategory: string); ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | \_request | OutgoingRequestMessage | | | transport | Transport | | | user | ClientTransactionUser | | | state | TransactionState | | | loggerCategory | string | |