Blue Sea Systems Dual Post CableCap I/O Pair, for Top-Mount Dual-Post Marine Batteries, 1/0, 105C

Overview

The Blue Sea Systems 4018 is a pair of square CableCap insulators for 1/0 battery cables on top-mount, dual-post marine batteries. It covers the terminal connection to help prevent accidental grounding at the battery, while keeping positive and negative connections easy to identify with one red cap and one black cap.

This pair is suited to battery installations where the cable lug lands on in-line dual posts and the connection needs a clean insulating cover that stays in place with a cable tie. It is suitable for environments up to 105°C and meets ABYC Small Craft Section E-9, USCG 33 Subpart I, and ISO 10133 requirements for preventing accidental grounding of battery terminals.

Key features

• Fits battery terminals with in-line dual posts on top-mount marine batteries
• Sized for 1/0 battery cable terminations
• Includes one red insulator and one black insulator for clear polarity identification
• Helps cover exposed terminal connections to reduce the chance of accidental shorting at the battery
• Suitable for use in environments up to 105°C
• Secures with a cable tie for a tidy installation; cable tie is not included
• Meets ABYC Small Craft Section E-9, USCG 33 Subpart I, and ISO 10133 requirements for prevention of accidental grounding

Compatibility and fit

This insulator pair is made for top-mount batteries that use in-line dual posts rather than standard automotive posts, wing-nut style terminals, or single-stud connections. The 1/0 cable size matters here, so it is best matched to heavier battery cables commonly found on house banks, engine starting circuits, and other high-amperage DC runs on board.

It is a good match for boat owners replacing worn terminal covers or finishing a new battery installation where exposed lugs need insulation without changing the existing cable layout. On boats with tight battery compartments, this style helps keep the terminal area covered when tools, hold-down hardware, or loose gear are nearby.

Installation and setup

The caps sit over the terminated battery cable connection and are retained with a cable tie. That makes them straightforward to fit during a battery change, cable replacement, or electrical refit where you want the terminal area covered before the compartment is closed up.

Before ordering, check that your battery uses top-mount dual posts and that your finished cable assembly is built with 1/0 cable. If your system uses another terminal style or a different cable gauge, a different CableCap style will be the better fit.

What's included

• 1 red insulator
• 1 black insulator