Because the ear washing ball was originally used by the hospital to treat ear diseases, the water in the ear was absorbed after swimming. So it's called ear wash ball.

Ear washing balls are generally used to blow away dust from wet objects, such as removing dust from keyboards and circuit boards. In the laboratory, ear washing balls are mainly used to quantitatively extract liquid from pipettes and pipettes, and can also blow away powdery substances in closed containers.

Ear-washing ball is not only a special instrument in analytical laboratory, but also used in many occasions: repairmen in watch and precision instrument repair shops often take ear-washing ball to suck some alcohol and spray it on the surface of metal objects to clean parts; Photography lovers often use ear washing balls to blow away the dust on the lens surface and so on.

Extended data:

Method of absorbing solution with ear washing ball:

Hold the upper end of the pipette with the thumb and middle finger of the right hand, and insert the lower mouth of the test tube into the solution to be absorbed. Insertion should not be too shallow or too deep, generally in10 ~ 20 mm. Too shallow will lead to suction, and the solution will be sucked into the ear washing ball to pollute the solution. Too deep will lead to too much solution outside the tube.

Hold the ear washing ball with your left hand, blow out the air first, then connect the tip of the ball to the upper mouth of the pipette, slowly loosen the squashed ear washing ball, so that the solution can be sucked into the tube. First, suck in about 1/3 of the tube capacity, press the nozzle with your right index finger, take it out and moisten it for three times, then suck the solution above the scale, and immediately press the nozzle with your right index finger.

Baidu encyclopedia-ear washing ball