MyCoal Toe Warmers - max 5 hour life:
Non-adhesive format. Supplied in pairs. For use only in fully enclosed shoes. Not for direct application to skin. Position under and outside socks.

Specifications:
Dimensions: Contoured size - Length: 8.5 cm - Width: 6.5cm - Weight: 16 grams
Format: 5 hour life - No adhesive backing - Disposable
Temperature: Max: 60 Deg C. - Average: 38 Degrees C.
Manufacturer: MyCoal - Japan
Packaging: Pack includes 25 pairs of toe warmers.

Other suggestions for toes:
LT-TW: Ultra thin 6 hour toe warmer from Lotte.