Square D | A1B120 | Circuit Breaker | 20A | 1-Pole | 120V | 10kA | Bolt-On

The Square D A1B120 is a purpose-built 20A, 1-pole circuit breaker designed to protect 120V branch circuits with a robust bolt-on mounting. Built for maintenance, retrofit, and replacement, this unit delivers a dependable solution when your panel requires exact compatibility and a secure connection.

Key specifications at a glance

• Amperage: 20A
• Pole: 1-Pole
• Voltage: 120V
• Interrupting Capacity: 10kA
• Mounting: Bolt-On
• Part reference: A1B120

Why this breaker stands out

Designed for compatibility and dependable performance, the A1B120 is ideal when you need a precise match for your Square D panel. The bolt-on design provides a secure, vibration-resistant connection that stays put through load fluctuations, making it a smart choice for retrofit projects and field replacements where panel alignment and mounting style matter.

Use cases and practical applications

• Residential and light commercial circuits where a single 120V branch needs reliable protection
• Panel maintenance and retrofits where the A1B120 matches the panel’s rated configuration
• Replacement of a failed or worn 20A, 1-pole breaker in compatible Square D installations

Installation and compatibility tips

Before ordering, confirm fit and ratings to ensure seamless integration. The part number A1B120 is the most trustworthy reference for compatibility with your Square D panel. If you’re replacing an existing unit, verify that the panel location accepts a bolt-on 1-pole breaker and that your circuit requires a 20A, 120V protection with a 10kA interrupting capacity.

What problems it solves

• Prevents overcurrent damage on 120V branch circuits by providing precise overcurrent protection
• Delivers a secure, durable mounting solution that stays aligned through electrical load changes
• Offers a straightforward path for maintenance, replacement, or retrofit without overhauling the panel

How it compares to other options

Compared to plug-on variants, the Bolt-On A1B120 provides a sturdier mechanical connection, which can be preferable in panels subjected to vibrations or higher ambient temperatures. Its 10kA interrupting rating offers strong protection for typical residential circuits, while the 1-pole configuration is ideal for individual 120V circuits rather than multi-pole 240V layouts.

Buying confidence and next steps

If your project requires exact compatibility, a 20A, 1-pole, 120V breaker with a bolt-on mount, the Square D A1B120 delivers the right combination of safety, reliability, and ease of installation. Add it to your cart to complete your repair, retrofit, or replacement with assurance.