The DR-200-set is a 2 wires system, that includes push button panel and AR-200 adapter, which adapt between the DR-200 push button panel to the main telephone line coming to the house allowing the homeowner to grant access and speak with the visitor through any telephone in the house including wireless. *DR-500 / AV model is avilable to order, connet directly to 5-wires intercom handset Features: - Lighted or non lighted push button available - Out / in door installation - Simple to operate and program - Smart looking durable design - Designed for mounting on a wall, or over a Single-gang junction box - Silver or anodized bronze color available