4.0Ah vs 5.0Ah vs 6.0Ah
Same fit: these run the same tools
Lowest price we track at UK retailers, updated daily. We may earn a commission
They differ in 4 of 5 areas
Same tools, so this is about size, weight and cost. No overall winner: pick the size that suits the job.
EnergyThe 6.0Ah stores 50% more than the 4.0Ah: 72Wh vs 48Wh.
PriceThe 4.0Ah is the cheapest of the three today, at £39.95.
Price per Ah6.0Ah £8.33, 4.0Ah £9.99, 5.0Ah £11.99.
Chemistry4.0Ah: Li-ion (cylindrical); 5.0Ah: Li-ion; 6.0Ah: Li-ion (cylindrical).
Good to know
Same toolsAll three fit every Milwaukee M12 tool.
Weight0.4 to 0.42kg: too close to call.
Same chargersM12-18FC, M12-18GBC4, C12C, M12C4 and M12-18AC charge all three. Charge times are in the specs below.
Energy
M12B4
48Wh
M12HB5
60Wh
M12B6
72Wh
Maker figure, or volts × Ah where they don't publish one. Ah and Wh explained ›
Weight
M12B4
0.4kg
M12HB5
0.42kg
M12B6
0.4kg
Within 0.1kg: too close to call.
Price per Ah
M12B4
£9.99
M12HB5
£11.99
M12B6
£8.33
Lowest price we track ÷ Ah. Full specs
M12B4M12HB5M12B6
Voltage12V12V12V
Capacity4.0Ah5.0Ah6.0Ah
Energy48Wh60Wh72Wh
Weight0.4kg0.42kg0.4kg
Energy for its weight120Wh/kg (worked out)143Wh/kg (worked out)180Wh/kg (worked out)
ChemistryLi-ion (cylindrical)Li-ionLi-ion (cylindrical)
Cell typeNot listedNot listedNot listed
Fuel gaugeYesNot listedYes
Size (L × W × H)Not listedNot listedNot listed
Charge time, M12-18FC, M12-18GBC452 min1 hr 15 min1 hr 35 min
Charge time, C12C, M12C41 hr 20 min1 hr 50 min2 hr 10 min
Charge time, M12-18AC1 hr 55 min1 hr 50 min2 hr 45 min
Lowest price£39.95£59.95£49.95
Specs from each maker's own documentation. "Not listed" means the maker doesn't publish it or we haven't found it yet; it never counts as a difference.
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