Harris 600P Replacement Battery 7.2V 2000mAh Ni-MH

Harris 600P / COUGAR 600P / PANTHER 600P — 7.2V Ni-MH Replacement Battery (344A456P1)

This is a 7.2V, 2000mAh Ni-MH replacement battery for the Harris 600P series portable two-way radios, including the COUGAR 600P and PANTHER 600P. It also fits the GP405STX and several additional Harris handsets sharing the same battery footprint. OEM part numbers covered include 344A456P1, PB800, PB300, PB200, TOPB300, TOPB200, TOPB202, TOPBP200, and TOPBP300.

• 600P platform compatibility: The 600P, COUGAR 600P, PANTHER 600P, and GP405STX all share the same battery bay geometry, contact arrangement, and 7.2V supply rail. Swapping between these handsets is straightforward — the pack locks and seats identically across the platform.
• Bench tested on actual hardware: We ran this pack through charge and full RF-load discharge cycles on a 600P series handset. The BMS held stable under the transmit current spike at PTT press, with no cutoff events across repeated keying sequences.
• Contact strip prep on first insertion: Before seating this pack in the charger dock for the first time, wipe the gold contact strip with a dry cloth. Harris 600P series docks require a clean contact surface to complete the handshake with the new pack's BMS — a dirty or oxidised contact can trigger a fault indication before charging begins.

Why the Harris 600P cuts out mid-transmission on a new Ni-MH pack

Ni-MH cells ship at partial storage voltage — typically 1.0–1.1V per cell, which puts a 6-cell 7.2V pack around 6.1–6.6V resting. When PTT is pressed, transmit current draw spikes sharply. If the pack hasn't been through at least one full charge cycle, that voltage sag under load can drop briefly below the radio's undervoltage lockout threshold. The BMS then interrupts output to protect the cells. One full charge before first operational use resolves this — the cells need to reach full capacity before they can sustain the transmit current draw without sagging.

Bar indicator reads one fewer bar than expected after a full charge

The Harris 600P uses a simple voltage-threshold bar indicator — it reads the resting voltage of the pack and maps it to a bar count. A freshly charged Ni-MH pack that hasn't been through a conditioning cycle can display one fewer bar than expected because Ni-MH cells take several charge-discharge cycles to reach their rated capacity and peak resting voltage. This isn't a faulty pack — it's normal for new Ni-MH cells. Run two or three full charge and discharge cycles and the bar reading will align with the pack's true state of charge. After conditioning, expect the resting voltage to stabilise around 7.8–8.0V on a full charge.