APPLICABLE SCENARIO: Speed controller is suitable for electric bicycles, electric tricycles and electric motorcycles. Suitable for a variety of direct current motors and other applications, can adjust motor speed well 2. STRONG AND TRUSTED: This controller is made with a quality circuit board for a longer service life, equipped with electric door lock, you can use with confidence 3. STRONG MATERIAL: The controller enclosure is made of aluminum alloy, adopt groove design, possess good heat dissipation, can protect the internal circuit and avoid thermal overload 5. LOW FAILURE: The line and interface are made of quality plastic and aluminum alloy material to ensure a low failure rate during long term use. Item Type: Direct Current Motor Speed Controller Material: Plastic and aluminum alloy. 1 x Speed Control Switch 1 x Charging Port 2 x Keys 1 x Controller. Main voltage should match. We will reply your message within 48 hours. If you do not receive our reply within 48 hours, pls. Post a message again because sometimes our message system may block some emails. If you are satisfied with our service, pls. Our aim is to provide Level Customer Service, your recognition will encourage us greatly and serve you better. We strive to keep all our customers satisfy. We will do our up most to exceed your expectations in customer service, communication and dispatching of your orders.