Blue Sea 8240 DC Analog Voltmeter - 2-3/4" Face, 18-32 Volts DC 
DC Analog Voltmeter
Simple 2-wire connection
Meter Senses Powers from same connection
Backlit meter face
WARNING: This product can expose you to chemicals including di(2-ethylhexyl)phthalate (dehp) which is known to the State of California to cause cancer, birth defects or other reproductive harm. For more information go to P65Warnings.ca.gov.