Blue Sea M-Series 300A Isolator Switch

(Exc. 20% VAT)
Order now, dispatch 7-14 days
Blue Sea
Product Details

Blue Sea battery cut out switch, finished in red with a removable on off two position knob. Rated to 300A for isolating a single 12v battery. Ignition protected safe for installation on 12v systems in automotive applications and also extremely popular aboard petrol powered marine craft.

The case design allows surface, front panel or rear panel mounting and comes with an isolating cover with snap-on sections, to protect the rear cable studs.


  • Switch type: Single circuit ON-OFF
  • Colour: Red
  • Switch positions: 2
  • Battery combine: No
  • Alternator field disconnect: No
  • Maximum voltage: 48V DC
  • Continuous rating: 300A
  • Intermittent rating: 500A (5 min)
  • Cranking rating: 10 sec 1500A
  • Cranking rating: 1 min 775A
  • Battery inputs: 1
  • Cable clearance for 4/0 AWG cables: 1.12in (28.45 mm)
  • Cable size to meet ratings: 4/0 AWG (120mm²)
  • Mounting holes accept: 10mm screw
  • Terminal stud size: 3/8 - 16  (M10)
  • Terminal stud torque: 120 lb/in (13.56 Nm)
  • Switch weight: 290gr (0.65lb)
Delivery Schedule

We are Official Suppliers of a wide range of products that are supplied by various distributors in the United States. The delivery times for these products is currently 10-40 days. This is because we place stock orders with these suppliers and then combine all required products into one monthly shipment, which we place on or around the 16th of each month and have shipped by the 20th of the month.

If you place an order prior to our monthly stock order going in and so long as the goods are available in the US, we are usually in a position to ship your order within about 7 days of the 20th of that month, if however your order is placed after our monthly stock order, then we might not be in a position to dispatch your order until around 37-40 days later.

If these timescales will take longer than your requirements, please don't place an order for them with us. If you do place an order, we will contact you to confirm your order items and inform you about any other requirements, thank you for your understanding.