. Otto 128 Hz tuning fork (on C3 pianos). Emergency specialists and paramedics use this fork to locate fractures. Especially this fork is the most nitric oxide. This is a gas that occurs naturally in the body. Nitric oxide has several functions in the body. It acts as a messenger between cells, neurotransmitters and hormones. It helps dilate blood vessels, supports a healthy heart, enhances brain strength, improves sexual health, and improves blood flow. The 128 Otto tuner is especially effective on rib heads, thoracic spine, sternum and geraniums. Two Otto tuners tap gently on the knee and grip the ear, creating a beautiful long-lasting bass that's perfect for grounding and relaxation. To listen, hold the 128 Otto tuner against the stem, then gently tap your knee or tap the weights on the pad. Bring the tuning fork to your ear and adjust the distance by tone. Hold a prong about 1 inch from the left ear and about 1 inch from the right ear. This creates a long-lasting tone. Otto tuners are available in three different frequencies: 32, 64 and 128 Hz. It is recommended to start with Otto 128. These tuning forks are made of aluminum, a soft metal that is great for harmony and sound healing. Due to this softness, you may notice occasional small marks or scratches. The fork will not be damaged, nor will it be tuned. This can happen during manufacturer packaging. We provide safe storage and careful care when handling.