Siemens | E21B020 | Circuit Breaker | 1-Pole | 120V

Meet the Siemens E21B020 — a purpose-built 1-pole 120V circuit breaker designed for maintenance, retrofit, and replacement projects where exact specifications matter. This model keeps your electrical system protected with a form-fit, function-driven design that mirrors your existing panel hardware.

Precise compatibility you can trust

The E21B020 is identified by its part number, making it the most reliable reference when confirming fit. Before you order, verify that the pole count and voltage align with your panel’s requirements. Using the exact part number minimizes guesswork and reduces the risk of mismatches that can lead to tripping or unsafe connections.

Key details

• Poles: 1-Pole
• Voltage: 120V
• Part number: E21B020

Why it matters for your electrical projects

Whether you’re performing a routine replacement after a fault, retrofitting a circuit to support additional loads, or maintaining an aging panel, using the correct, single-pole 120V breaker is crucial for consistent protection and safe operation. The E21B020 delivers dependable interruption for a single hot leg, helping to safeguard downstream devices and wiring without unnecessary complexity.

How to use it confidently

• Always confirm fit and ratings against your panel’s manufacturer specifications before ordering.
• Keep the part number E21B020 on hand as your primary reference during procurement and future maintenance.
• Use this breaker for standard 120V circuits that require single-pole protection in residential or light commercial environments.

Ideal for

electricians, technicians, homeowners, and facilities managers who need a reliable, NEMA-compatible 1-pole 120V circuit breaker for maintenance, retrofit, or replacement work, with a clear, unambiguous reference in the form of the E21B020 part number.