There are many ways to heat sake.  You can put a tokkuri filled with sake into a microwave oven for approximately 60 seconds; you can place your tokkuri into a pot half filled with water and heat it on a stove - old school but takes more time; or you can try modern style and use a sake heater. Nothing wrong with any way you heat sake.

Sake Warmer Twinbird Tw 4418b Osake Kan Portable Machine (Kitchen)

List Price: $59.24 USD
New From: $59.16 USD In Stock
Used from: $57.01 USD In Stock

Electric Sake Warmer Genuine Mino Ware Minoyaki (Kitchen)

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New From: 0 Out of Stock
Used from: Out of Stock