OptiMate Battery status / charge system monitor for 12V lead-acid & 12.8V lithium-ion, with in-line SAE connectability - MONITOR O-125

The OptiMate MONITOR O-125 is a compact battery status and charging system monitor that connects directly to a standard SAE 2-pin battery lead. It continuously displays the state of charge of your 12 V battery — including lead-acid (AGM, GEL, STD) and 12.8 V lithium-ion (LFP) types — and confirms whether your vehicle’s charging system is operating correctly. 

Features and Benefits

• SAE quick-connect charge port — simply plug in the monitor to any SAE 2-pin lead for instant battery status feedback. 
• Length: 15cm cable 
• Operation: 2 automatic Modes – Battery charge level monitor (single LED blink mode) & Charging system test (arrow mode).
• Vehicle storage: 4 LEDs cover ‘full to empty’ voltage range of all 12V batteries, including higher voltage AGM for power sport (3th √ LED ≥ 12.7V). LED matching charge level blinks every 3 seconds (long term draw less than 0.2mA).
• Vehicle running: LED arrow mode activates when charge voltage reaches ideal charging voltage; up to minimum 13.5V or ideal range 14V+.
• 16 AWG / 1.31 mm² cable (cable diameter) — robust wiring that supports accurate voltage sensing.
• Thicker insulation for better protection. SPT-2 (1.2 mm) — adds durability and abrasion resistance for long-term use.
• Current rating: 10A max
• Weather- and dirt-protected SAE connection system, including rubber sealing cap and shroud — helps safeguard the SAE connectors from water, dust and corrosion, making it reliable for outdoor use. 
• Rated for –40 °C — remains flexible and operational even in very low temperatures. 
  

What’s in the box

• 1 × OptiMate MONITOR O-125 V2 battery monitor (SAE-to-SAE, 15 cm)
• Weather-proof rubber sealing cap for the SAE connector 

Warranty

• 3-year limited replacement warranty