Sauna scent Birch is made from pure Finnish dried birch leaves. The package contains four birch leaf sachets, which when used in sauna water bring a genuine birch scent to the sauna. Prepare your sauna water by steeping the sachet in warm water. Use as you would regular sauna water and smell the pleasant birch scent in your sauna. One sachet is enough for several sauna sessions, as long as you let the sachet dry in between.