We have tested the compatibility after making the mold and installing it in the phone. Please use the original charger to achieve the best charging effect. 【Safety Features】:The battery is equipped with insulating separators and IC smart chips inside,Equipped with multiple safety mechanisms like overcharge protection, over-discharge protection, short-circuit protection, and thermal management systems，It automatically reduces frequency or cuts off power in high-temperature environments, and the operating temperature range covers -20℃ to 60℃. Full box) Astell and Kern AK70 MKII High-Resolution Digital Audio Exact Fit Replacement: Precisely matches AK70 and AK Jr models. Universal Compatibility: Suitable for multiple Iriver players and cubes A Suggestion to Increase Battery Life : 1., Do not over discharge or idle for a long time, the battery is easy to expansion., 2., Do not keep the battery in a low battery state for a long time. 【Precise compatible product model】: This battery is compatible For iRiver Astell & Kern AK70, and the battery model is AK70 MKII. 【Fast Charging & Efficiency】:Adopting intelligent fast charging technology, it automatically matches the optimal current, and the charging speed can be increased by 30%，When the battery is fully charged, it will automatically cut off power to prevent battery swelling. Battery model: AK70 MKII Compatible Products：Compatible For iRiver Astell & Kern AK70 2., After replacing the battery, please consume all the power of the battery, then use the original charger to charge for 8 hours, and cycle the same operation 3-5 times to activate the properties of the battery to achieve the best use effect., 3., Please use the original charger and data cable to charge the battery., 4., Long term depletion or full charge storage can accelerate battery aging. 【Cycle Life & Durability】: It adopts A-class lithium-ion/polymer battery cells, featuring high energy density and long cycle life. Astell&Kern SP3000 High Resolution Audio Player - Black High-quality batteries can endure 800 to 1000 cycles or more,Retains up to 80% capacity after 800 full charge cycles. IRiver Player Battery New Upgraded Player Battery Compatible For IRiver Astell & Kern AK70 AK70 MKII MP3 Player,with Full Tool Kits Ultra-Power 4800mAh AK70 MKII IRiver AK70 MKII MP3 Player Battery
