The UnderWarmer is a single-use, compression fitted base-layer vest. 8 Heat Packs are built-in and will activate within minutes of removing from its packaging. When ready to use, simply remove The UnderWarmer from its packaging. Upon opening, heat activation begins and will take approximately 30 minutes to reach its maximum temperature of over 100f/38c.
The UnderWarmer heated vest is convenient, super comfortable and best of all- it works really well! UnderWarmer was specifically designed to be affordable and convenient for the everyday guy or gal spending a long day in the cold.
