Nest eye cleaning test bed using seed length difference to sort for all kinds of seeds or length grading for a small amount of seed. Cylinder with pressed steel nest eye (pit) after the volume is cylindrical, according to the length of the seed to be processed to  determine the size of the difference between the size of nest eye diameter; nest eye roller by horizontal installation , adjustable tilt angle 0-30 ; barrel U-shaped slot angle within plus or minus 300 is adjustable; the machine's main function is through different length seed in the separation test, you can obtain distribution about the batch of seeds on the percentage of length and size , which provide the basis data for further research seed characteristics.