16 Pcs Hot Massage Basalt Stone Volcanic Stones Kit Rock SPA Oiled Massager Salon16 Pcs Hot Massage Basalt Stone Volcanic Stones Kit Rock SPA Oiled Massager Salon 16pcs Hot Massage Stone Basalt Stones Set Rock SPA Massage Box Kit Features 1. We know that heat retention is important to give you and your clients the best hot stone therapy experience These stones are large enough to retain the heat for a long and relaxing massage Heat from 15 to 40 minutes depending on intensity required. 2. A succinct and informative course in