This 50 piece basalt stone set is competent for a one hour full body massage.. It has everything the hot stone therapist needs to perform full body treatments. We use 100% Natural Black Basalt and white marble rocks as the only materials, all stones were polished by traditional handcraft, no wax, dyestuff, chemicals were applied during the production. The natural bamboo box is handmade to provide an efficient storage place for your stones. • 2 Extra large ovular basalt (1 for sacral, 1 for stomach): 4.5" x 3" x 1.1"; 6 Large flat ovular basalt size (4 for backside, 2 for thigh): 3" x 2.3" x 1" • 14 medium flat ovular basalt size (4 for leg, 4 for arm, 2 for palm, 4 foot) : 2.6" x 1.9" x 0.7"; 6 Small flat ovular basalt (2 for forehead, 2 for head crown, 2 for hindbrain):1.5" x 1.2"x 0.7" • 6 Round compressed basalt (for bed heater under the backside) : 1.7" X 0.3" • 6 Small circular facial basalt: 0.9" x 0.3"; Toes (for feet); 2 Small ovular white marble (for cool therapy) : 1.7" x 1.2" x 0.3" • Packed within a bamboo box.