Enersys 12V Sealed Lead Acid Battery NP4-12 — 4Ah with 0.187" Fast-On, AGM Maintenance-Free

The EnerSys Genesis NP4-12 is a compact, maintenance-free 12V sealed lead acid (SLA/AGM) battery rated at 4 amp-hours with a 0.187" Fast-On terminal for quick installations.

This battery delivers dependable, spill-proof power in a small package suitable for backup systems, security devices, emergency lighting, and portable electronics. Built by EnerSys to the Genesis NP series specifications, the NP4-12 combines rechargeable SLA chemistry with an absorbent glass mat (AGM) design so it can be mounted in virtually any orientation while resisting vibration and shock.

How does this battery fit into tight spaces and small devices?

The NP4-12’s compact footprint and modest weight make it a natural choice when installation space is limited. At just 3.54" long, 2.76" wide and 4.21" high, it slips into battery compartments that larger cells cannot.

• Dimensions: 3.54 x 2.76 x 4.21 inches for slim installations
• Weight: 3.75 lbs — easy to handle and install
• Mountable in any position thanks to sealed, spill-proof construction

What connectors and compatibility should I expect?

The NP4-12 ships with a 0.187" Fast-On (also called 187 or 4.75mm) terminal that enables fast, reliable connections with a wide range of chargers and devices. This common Fast-On sizing fits many commercial and consumer products, reducing the need for adapters.

• 0.187" Fast-On terminal for quick, tool-friendly hookup
• Works with standard 12V SLA chargers and compatible systems
• Common in alarm panels, emergency lighting, and UPS modules

How durable and low-maintenance is the EnerSys NP4-12?

The NP4-12 uses AGM technology that traps electrolyte in glass mats, making the battery leak-resistant and maintenance free. Its rugged construction helps it tolerate vibration and moderate shocks, making it suitable for fixed and portable applications.

• SLA/AGM sealed design — no topping up of water required
• Resists shocks and vibration for reliable operation in mobile or industrial settings
• Full one-year warranty from EnerSys for added confidence

What are typical use cases and runtime expectations?

Rated at 4 amp-hours, this battery is designed for short-to-moderate runtime duties such as standby power, periodic operation, or low-current continuous loads. Actual runtime depends on the device’s draw and temperature, so size batteries conservatively for critical backup roles.

• Suitable for alarm systems, emergency lights, medical backup devices, and small UPS units
• Rechargeable — ideal for repeated charge/discharge cycles in standby service
• Perform better when stored and operated at recommended temperatures

Who is this for? The EnerSys Genesis NP4-12 is aimed at technicians, facilities managers, and DIYers who need a reliable, compact 12V SLA battery with a common Fast-On terminal. If you require a sealed, maintenance-free power source for security panels, emergency lighting, small UPS units, or portable equipment where space and vibration tolerance matter, the NP4-12 provides a straightforward, manufacturer-backed option with a one-year warranty.