Replacement Controller for RCL-50 and some RCL-100 spotlights. The ACR Master Controller can restore function or add features to RCL-50 and RCL-100 series spotlights. This master controller was included with RCL-50 and RCL-100 with soft ON/OFF and XRCiZ features. For RCL-100 spotlights without these features, the installation of a master controller will add functions. Controls soft ON/OFF and light rotation speed features and provides optimum voltage for brightest performance. Can perform up to six different duties; controls searchlights, winches, and other devices. Key Features Replacement controller for ACR spotlights Compatible with RCL-50 and RCL-100 series spotlights (can be added as an upgrade to RCL-100s not supplied with master controller) Ensures optimum voltage for best performance Soft ON/OFF powers light gradually for longer bulb life Provides exclusive XRCiZ feature that rotates spotlight automatically to confirm electrical contact are functional and keep bearing surfaces free of corrosion Compatible with 12V and 24V systems Includes 8 inline connectors Does not include coax cable (RG-59) Dimensions: 2.8"L x 3.0"W x 1.6"H