Downloading Srelay 0.4.8 for Mac from the developer's website was possible when we last checked. We cannot confirm if there is a free download of this app available. We recommend checking the downloaded files with any free antivirus. This free Mac application is a product of Tomo M. The software lies within Internet & Network Tools, more precisely Network tools.
From the developer:
Srelay is a socks 4/5 protocol proxy server. Supports socks connect/bind request in the protocol v4, v4a, and v5. Supports socks server chaining with both v4 and v5 servers. Supports Username/Password authentication in v5 (not recommended). Supports IPv6 as well as IPv4.
You may want to check out more software for Mac, such as IPNetShareX, PPPoE Connector or Remote Connections Manager, which might be related to Srelay.