Circular saws have one blade mounted right on the axle of the engine. The saw has a voltage of 18 volts and weighs 4.1 kg, so it's not that heavy to carry around.
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Bosch Professional GKS18 V - LI 18 V Li - Ion Cordless Naked Circular Saw
Wickes
Bosch Professional GKS 18 V LI Cordless Circular Saw - Bare
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