Amazon.com : Clarity Amplified Telephone Ringer With Visual Indicator (SR200) : Loud Telephone Ringer : Health & Household
Federal Signal TelCom® TELH-120 Telephone Extension Ringer Device, 120 VAC, 0.24 A, 100/110 dB Sound Level, Wall Mounting, Gray, Specifications Met: CSA Certified, FCC Approved, UL Listed | SMC
Amazon.com : Acenis Big Button Phone for Seniors - Corded Landline Telephone - Large Buttons and One-Touch Dialling for Visually Impaired - 80 dB Amplified Ringer for Hearing Impaired, Ergonomic Non-Slip Grip :