To fit mattress size:
Single : Width 90cm x Length 190cm
Double : Width 135cm x Length 190cm
King : Width 150cm x Length 198cm
Superking : Width 180cm x Length 200cm
Having liked a previous purchase of a sheet, I sent for two more. Most sheets seem to be 50% cotton and 50% polyester but your 80% / 20% is much better and doesn't "bubble".
From United Kingdom