Square D QOB120GFI 20A 1P 120V Circuit Breaker, QO, GFCI, Bolt-On | AmpState

The Square D QOB120GFI is a 1-pole, 20 A, 120-volt GFCI circuit breaker designed for bolt-on mounting in Square D QO panelboards and load centers. Built for retrofit projects and ongoing maintenance, this part keeps your electrical distribution consistent when replacements are needed, so you can protect circuits without changing the entire panel lineup.

Key benefits at a glance

• GFCI protection helps guard against electrical shock by detecting ground faults on the protected circuit.
• Bolt-On mounting delivers a secure, straightforward installation in compatible QO enclosures.
• 20 A, 1-pole, 120 V specification makes it a precise match for branch circuits requiring dedicated overcurrent and ground-fault protection.
• QO family compatibility ensures reliable performance within existing Square D distribution systems.
• Part number stability ideal for retrofit work where the QOB120GFI keeps your replacement catalog consistent and your planning predictable.
• Avalable from AmpState with support to confirm fit and compatibility for your panel.

Why technicians and facilities managers choose the QOB120GFI

When upgrading protection in an established panel, compatibility and installation speed matter. The QOB120GFI is a direct fit for QO panels that support bolt-on breakers, offering a reliable, code-compliant solution without reconfiguring your distribution layout. Its 1-pole design is ideal for single-circuit protection, while the GFCI feature adds an essential layer of safety in areas where moisture or sensitive electronics are present. For retrofit projects, sticking with the same part family and part number simplifies ordering, stocking, and future maintenance.

Ideal use cases and practical applications

• Retrofits in existing Square D QO panelboards where GFCI protection is required for a branch circuit.
• Maintenance planning where maintaining a consistent part number minimizes change management and procurement steps.
• New installations that reuse or extend an existing QO distribution scheme while adding ground-fault protection.

Compatibility and installation tips

Before installation, verify that your panel is a QO-type enclosure and supports bolt-on breakers of the QOB series. The QOB120GFI is specifically designed for 120V circuits and 20A protection, so match to the circuit rating and voltage in the panel rating. If you’re unsure about fit, AmpState can assist in confirming compatibility and providing the right part for your setup.

For help matching a part number or confirming compatibility, send a message and AmpState will help you confirm fit.