[Home](./index.md) > [puppeteer](./puppeteer.md) > [Protocol](./puppeteer.protocol.md) > [DOMSnapshot](./puppeteer.protocol.domsnapshot.md) > [DOMNode](./puppeteer.protocol.domsnapshot.domnode.md) > [systemId](./puppeteer.protocol.domsnapshot.domnode.systemid.md) ## Protocol.DOMSnapshot.DOMNode.systemId property `DocumentType` node's systemId. Signature: ```typescript systemId?: string; ```