its this stuff in the image alongside. its fairly aggressive (you definitely need to wear gloves while you work with it), but if your machine has been neglected it has got the grunt to get the job done
we dont sell it online as you have to move it with a courier that specialises in the transportation of hazardous goods so the game isnt really worth the candle
you will be able to procure a strong alkali solution pretty much wherever you live anyway, just not at a supermarket where they have refined to a fine art the practice of selling diluted consumer grade drivel in very small quantities for an exceptionally high price.