All size and length conveyors are adjustable. Stainless steel is available. 
Standardized dimensions: 

width 150mm: L1500 / L2300 / L2500 / L2700 / L3000 / L3500 mm
width 200mm: L2300 / L2500 / L3000 / L3500 mm
width 250mm: L2500 / L3000 / L3500 / L4000 mm