Dual Battery Isolator 12V 300A VSR, LCD, Manual Auto

Dual battery isolator 12V 300A keeps your starting battery protected while efficiently charging an auxiliary battery for RV, truck, boat, or off-grid setups. A voltage sensitive relay with LCD screen shows both battery voltages in real time and supports lithium and lead-acid systems. Switch between automatic VSR operation and manual mode to manage power with confidence in demanding outdoor conditions.

• Delivers 300A high-current split charging for high-capacity dual-battery systems


• Supports lithium and lead-acid batteries with adjustable start/stop voltage settings


• Switches to manual mode to use the auxiliary battery to assist a depleted main battery


• Prevents rapid cycling with an adjustable 3–60s delay to reduce wear


• Displays dual battery voltage (4.5–20V) for fast diagnostics and system checks

Built for real-world installs, this smart battery isolator adds overvoltage and undervoltage protection in a compact, rugged housing designed to handle vibration, dust, and rough use. Use it as a split charge isolator for vehicle or marine electrical systems where stable power matters—camping gear, winches, lighting, fridges, and accessories. If you want cleaner charging control and clearer voltage visibility without guessing, grab yours today.

• Rated voltage/current: DC 12V, 300A


• Voltage display range: 4.5–20V


• Delay time: adjustable 3–60 seconds


• Material: PA6


• Dimensions: 3.5 x 3.5 x 3.1 in (90 x 90 x 80 mm)


• Net weight (with accessories): 0.9 lb (0.42 kg)


• Color: Black