We have AA batteries and AAA batteries, but why is there no single A battery? - Quora
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6v Batteries - Batteries - The Home Depot
Amazon.co.uk: 6 Volt Lantern Battery
6v Batteries - Batteries - The Home Depot
Diall Alkaline Batteries Non-Rechargeable Mn21 Battery Pack Of 1 | Diall | UK
AA Heavy Duty LED Torch AA3881 – 180 m Beam Distance, Adjustable Base 6 Angles, 120 Lumens, Weatherproof, Batteries Included : Amazon.co.uk: DIY & Tools