WirthCo Battery Doctor Mini Master Rotary Dial Disconnect Switch with On/Off Knob and Bottom Cover is designed for applications up to 48 Volts DC and can be used with 1 or 2 batteries. This disconnect switch is ISO 8846 approved. It has a continuous rating of 300 amperes, intermittent rating of 1000 amperes/5 seconds and crank rating of 700 amperes/10 seconds. Has a knob operated on/off configuration and a bottom cover. The dimensions are 69 millimeters by 69 millimeters by 75 millimeters high. For over 30 years, WirthCo has been a prime manufacturer of practical products for making life easier safer. California Prop 65 - Warning, This product contains chemicals known to the State of California to cause cancer, birth defects or other reproductive harm.