Newly Designed Updated Model for 2022 - Featuring a Brass Diaphragm and All Soldered Wire Connections Redesigned to eliminate connectivity issues and increase reliability allowing you to make electronics projects like Crystal or Transistor Radios without concern for issues plaguing lower quality models High 20,000 ohm impedance with resistance over 20 million ohms and a capacitance of 15,000 pf Rated Sensitivity of 57db at 1KHz in the frequency range from 200 to 8,000Hz New Black Wire Upgraded Piezoelectric Earphone with Classic style highly sensitive molded earpiece and 42-in twisted wire with pre-tinned bare wire connections ***Newly Designed Updated Model for 2022***
Brass Diaphragm and ALL soldered wire connections for improved connectivity and reliability

Redesigned to eliminate issues previously found in many piezoelectric earphones Tin Diaphram has been Upgraded to Brass
Conductive Glue (used on lower models) has been replaced with all soldered connections Black Wire is Specific to the upgraded 2022 version

Perfect to make electronics projects like Crystal or Transistor Radios
High 20,000 ohm impedance with resistance over 20 million ohms and a capacitance of 15,000 pf
Rated Sensitivity of 57db at 1KHz in the frequency range from 200 to 8,000Hz
Classic style highly sensitive molded earpiece with 42-in twisted wire with pre-tinned bare wire connections
Classic PiezoElectric Crystal Earpiece for DIY Electronics Kits

Ceramic Earphone Crystal Ear Piece for Transistor and Crystal Radios, Sensitive Electronics Projects, Lab research and other DIY experiments requiring a very sensitive high impedance earpiece.

Piezoelectric earphones are also known as crystal earphones, ceramic earphone, and piezo earpieces are the most sensitive earphones. They are in fact many times more sensitive than even the most sensitive magnetic earphones, dynamic earphones, or electrostatic earphones that you may use on your iPod or iPhone. Sensitive earphones have a very high impedance, which is measured in ohms and should not be used directly with a modern amplified radio. Crystal Earphones are so sensitive and require so little power to operate that you can hear a small 'click' just by touching the two bare leads together.

Crystal radios will not work with modern earphones or 'earbuds' as they are designed to operate with amplified audio sources found in today's electronic devices. Crystal Earphones are used in the construction of the crystal radio and in some science experiments such as listening to electric fish.