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Amazon.com - EID DC31 Battery Adapter for Makita 18V Battery Convert to Replace for Dyson DC31 Type-B DC34 DC44 DC45 Animal 917083-01 Vacuum Cleaner Converter (Adapter Only)
Dyson 16.2V 20W Mini Motorhead for Dyson DC31 34 35 Vacuums 917096-06 – Primelec
Kingsener DC31 (fit type A) Li-ion Vacuum Battery For Dyson DC34 DC35 - BatteryMall.com