---
title: tls.client.tlsexts_list_sha
summary: null
url: >-
  https://www.fastly.com/documentation/reference/vcl/variables/client-connection/tls-client-tlsexts-list-sha
---

**Type:** STRING  
**Access:** read-only

**Available in:** recv, hash, deliver, log

A SHA-1 digest of the TLS extensions supported by the client as little-endian, 
16-bit integers, represented in Base64.