A creme-filled wafer, covered in an outer layer of chocolate or other various flavors.
Originally created by English company Rowntree's, it is now manufactured by Nestle in all markets except USA, where it is made under license by Hershey's.
In Japan, Nestlé has introduced over 200 different flavors since 2000, and they are often bought as regional or good-luck gifts as the brand name echoes the Japanese phrase “Kitto Katsu,” roughly translated as “surely win".