Natural Lava Basalt Stones:Each piece stone made of premium natural Lava basalt stones; this stone has great heat retention, give your body a warmer massage, perfect for Spa, Massage Therapy. 10 Pieces Small Stones: every piece stone has the same size:1.18 x 1.57 in(3x4x0.8cm), suit for feet, face, eyes and body. Ergonomic Design: The curve surface makes the stone joint to your skin closely, avoid the heat loss, natural lava basalt stone surface have will keep more heat energy, little size can be use on feet, face, eyes. Application: These Massage Stones can effective massage and warmer you muscle, give your body a deep relax, improving your blood circulation. It is suitable for the people who are often to use computers and mobile phones. Replacement Guarantee: The Massage Stones have a perfect quality, long lifetime.