Irritrol's TW-D-1 Single Valve AC Decoder comes from the Rain Master Twice Series. This decoder has the capacity to operate a single 24V AC Valve in any Rain Master Twice Series Controllers, and includes 4 electrical connectors. Irritrol has made their name as a brand by selling and marketing exclusively to the professional installer, as a result their products are geared to be dependable and durable. Irrirtrol is now making their products available to you through our website. If you are looking for a product line that will last year in and year out, Irritrol is the brand for you.