B31N1726 Battery for Asus TUF FX504 FX505 FA506 - Reliable 48Wh

In this review the reviewer examines the B31N1726 replacement battery designed for a range of Asus TUF and ROG-style notebooks. The bottom line: this is a practical, no-frills replacement battery for users whose original pack has degraded and who need a direct, compatible swap; its main selling point is reliable capacity and broad compatibility across many Asus FX and FA series laptops. The review focuses on fit, runtime, build quality and after-sale support to help a buyer decide if this 48Wh Li-ion pack meets their needs.

Key Features

• Direct compatibility: The pack is built to match the Asus B31N1726 form factor so it installs as a drop-in replacement for many FX504, FX505 and FA506 series laptops.
• 48Wh capacity: A 48Wh 4240mAh rating provides a predictable runtime of roughly 60 minutes under heavier loads, useful for short work sessions or emergency use.
• Quality construction: Brand new Li-ion cells with updated circuit boards and a smart chip give stable current output and help protect against overcharge and overdischarge.
• Safety certifications: The battery meets UL, CE, FCC and RoHS style safety expectations to reduce the risk of overheating and ensure compliant materials.
• After-sale support: A 30-day return policy plus a 12-month warranty and 24/7 email support provide reassurance if there are fitment or performance issues.

Who It's For

This pack suits owners of supported Asus TUF or FX series laptops who need a like-for-like replacement for a failing internal battery and who prioritise correct fit and factory-style safety protections. It is helpful for students, gamers or field technicians who require a quick swap to restore basic mobility rather than extend long all-day battery life.

Users who demand extended multi-hour unplugged use or want the absolute maximum runtime should look for higher-capacity or manufacturer-specified high-end options. Also, anyone uncertain about model fit should verify the listed compatible series and replace part numbers before ordering.

Pros & Cons

Pros

• Compatible with many Asus FX504, FX505, FA506 and FA706 series models for straightforward replacement.
• Stable 11.4V output and 48Wh capacity provide predictable short-term runtime for work or casual gaming.
• New cells, smart circuitry and multiple safety certifications give confidence in day-to-day safety and reliability.

Cons

• Runtime is limited to roughly 60 minutes under heavy use, so it is not a long-life upgrade for power users.

Specifications

Battery model	B31N1726 compatible
Battery type	Li-ion
Voltage	11.4V
Capacity	48Wh / 4240mAh
Cycle life	About 500 cycles
Runtime (approx.)	60 minutes per charge under heavier load
Warranty	30-day return, 12-month warranty

Our Verdict

The B31N1726 replacement battery is a sensible, cost-effective choice for owners of compatible Asus FX and FA series laptops who need to restore original runtime and fit. It is not a high-capacity upgrade, but its correct form factor, smart protection circuitry and safety certifications make it good value for users who want a trustworthy swap and a backed warranty.

Frequently Asked Questions

Will this battery fit my FX505 or FX504 laptop?
It is designed to be compatible with many FX504 and FX505 variants and related FA series models; confirm the original part number or shape matches B31N1726 before purchase.

How long will the battery last per charge?
The rated capacity is 48Wh (4240mAh) and typical runtime under heavier use is about 60 minutes; real-world time will vary with workload and power settings.

What warranty and support are included?
The product includes a 30-day return window and a 12-month warranty, plus 24/7 email support through the store order system.