If you own one of these systems and want to add another ringer this does the job. You do need to pair it with you doorbell units.
Optimize Viewing With CAVN Black Angle Mount For Ring Video Doorbell 1 2 3 4 - Adjustable 30 To 55 Degree Angle
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Wireless Doorbell Chime - AVANTEK Mini Waterproof, 1000 Feet Range, 52 Melodies & 5 Volume Levels With LED Flash
31 Review
Universal 24V 40VA Thermostat / Doorbell Transformer: Compatible with Honeywell, Nest, Sensi, Ecobee, Nest Hello, and Ring Doorbells
43 Review
π Adjustable Anti-Theft Video Doorbell Mount Bracket - No Drilling, Unobstructed Doorbell Motion Sensor - Ideal Mounting Accessories for Homes, Apartments, and Offices
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π‘ Hydrofarm Quantum QT400 Dimmable Ballast for 400W Grow Lights
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Wireless Electronic Ballast Interface Certified
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β‘οΈ Sunpark LC-12014T (1) FC12T9 32W Circline (1) 2D 38W (1) FC16T9 40W Circline (1) FC9T9 30W Circline Lamp Compact Electronic Fluorescent Ballast with Circline Lamp Plug 120V
7 Review
π‘ High-Quality Advance ICN-4P32-SC Electronic Fluorescent Ballast: Ideal for 4 Lamps, 32W T8, 120/277V
3 Review