Circular saws are well-tested and efficient tools when it comes to cutting things. The voltage amounts to 18 volts and isn't all too heavy at 2.5 kg.
Einhell Power X-Change 150mm Cordless Circular Saw - 18V Rotary Wood Saw, Tool-Free Adjustment, LED, Dust Extraction - TE-CS 18/150 Li Solo Electric Saw (Battery Not Included)
OnBuy
Einhell 4331220 TE-CS 18/150 Li Solo Power X-Change Cordless Hand-Held Circular Saw - Supplied without Battery and Charger, 25.0 cm*30.7 cm*17.4 cm
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