material from above 3 kinds of material, copper, brass, alluminum.
size: less than 20mm, +/-0.02mm ID and OD, +/-0.05mm length

The reason to choose us:

1, matured product, accurate in size, can keep good tolerance.

2, low price, we are using automatic machine to cut it.

after process such as press the hole, shrinking 1 end available.

3, good and fast service.