Better control of the tone of each frequency, can make the middle frequency warm and generous, the low frequency is full and flexible, and the high frequency is and not dry. Made of high- materials, strong, wear-resistant and durable. Ruby and sapphire dual needles, Ruby for LP records and Sapphire for 78-speed . Structure: Polarity: When the needle tip is horizontally (left + right), the phase of the output voltage of the left channel (L) and the right channel (R) should be the same. Stylus: Ruby+Sapphire The output voltage: When the frequency F is 1kHz, when the vibration V of the sound groove in the L or R direction is 3.54CM/S or the vibration of the transverse sound groove is 5CM/S, the output voltage should be within +/- 4DB relative to the specified value (250MV) (Ie: within the range of 200~300MV). Acupuncture pressure: When testing the tracking and electrical parameters of the cartridge, the acupuncture pressure should be measured within the range of 40 +/- 10MN. Note: Small objects, Keep from children to avoid being eaten by children. Colour: Black Material: Plastic Package Contents: 1 * Stylus Only the above package content, other are not included. Note: Light and different displays may cause the color of the item in the a little different from the real thing. The measurement allowed error is +/- 1-3cm.