In Finnair's website:
Marimekko amenity kit
When travelling in Finnair Business Class, you’ll get a personal amenity kit encased in a Marimekko cotton bag, designed exclusively for Finnair. The collection includes high-quality brand products for your refreshment, and Marimekko slippers are also available.
Are there really slippers in the J kits? I'll be flying AY soon and wish to know if I should bring my own slippers.