Dyson DC31 DC34 DC35 DC44 battery disassembly for replacement: Not Worth It. - YouTube
How to Disassemble Dyson Cyclone DC30, DC31, DC34, DC35, DC44, DC43H - YouTube
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Battery Dyson Dc31 Animal Dc34 Dc35 | Dyson Dc35 Battery Li Ion Type B - B 22.2v - Aliexpress