An electric pressure washer from Einhell that you can easily clean the stone slabs. It's a slightly smaller pressure washer with a weight of no more than 4.3 kg.
From Amazon
Einhell High-pressure cleaner TC-HP 90 (1200 W, max. 90 bar, output max. 372 l/h, carry-handle, water connection + integrated filter, complete with gun, hose, lance + nozzle)
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