Artisan Power Nortel Norstar T7406 Phones: Replacement Battery. 1650 mAh Nortel Norstar T7406, M2616CT, NT8B45, NTAB9628 and NT8B45AAAB Replacement Battery Replaces battery number NTAB9682, M7001 and A0845917. NiMH Rechargeable Battery Pack| 3.6 Volt | 1650 mAh | Cells Made in Japan Longer Lasting: 1650 mAh capacity rating 18% higher than the OEM batteries. Manufactured by Artisan Power, a leader in premium quality replacement battery packs.