Royal Canin's renal prescription diet is available in two variants called Renal Special and Renal Select. Renal Select is for cats who are slightly older or struggle with hard kibble due to other issues. Here, the kibble has a very thin shell which is crunchy, as cats like this crunchy texture. However, the inside is soft, so your cat won't have to struggle too much. Renal Special is for cats who have Azotaemia Chronic Kidney Disease, stages 2 to 4, and Chronic Kidney Disease with proteinuria, all stages.