Dual Relay Service

Dual Relay Service is also listed under the following categories: Standard Yellow Pages Heading (SYPH) Categories:

• Telephones Services Tdd/Tty Telephone Relay Service

North American Industry Classification System (NAICS) Categories:

• Wired Telecommunications Carriers > Tdd/Tty Telephone Services > Telephones Services Tdd/Tty Telephone Relay Service

Standard Industry Classification (SIC) Categories:

• Telephone Communications, Except Radio > Tdd/Tty Telephone Services > Telephones Services Tdd/Tty Telephone Relay Service