Brand New Defiant Wired 16VAC/30VA Doorbell Transformer Compatible with all Video Doorbells This Defiant Branded Wired 30VA Doorbell Transformer is ideal for new construction or replacement. It features a Low-Voltage wired design that is perfect for most wired doorbell installations. This 30VA transformer is compatible with smart video doorbells, Wi-Fi smart devices and more. ETL Certified to guarantee safety and quality.