In-line amplifiers can be used with most corded phones. They offer solutions for care facilities that might not have phone services compatible with amplified or captioned phones.
How an in-line amplifier works: The handset of the corded phone plugs into the in-line amplifier, allowing the handset to use the volume control and tone control on the in-line amplifier. The added volume and tone control makes it easier for a hard of hearing individual to hear on the phone.
Serene-Innovations-UA-50
ClearSounds-CS-IL95
To learn more about all available equipment, click on this link;
https://relay.utah.gov/available-telecommunications-equipment/