It depends on what the saw will be used for. You can purchase a floor saw, or a handheld saw. Both are driven by either petrol, electricity or in the case of floor saws, diesel.  A handheld saw will be for cutting to a depth of up to 143mm, whereas a road floor saw’s normal depth of cut would be 245mm. There is equipment available with  cutting depths of up to 1200mm. There are many brands available on the market. Diatech stocks the Stihl and Husqvarna saw range.