double end tool的用法和样例：
- double end tool post wrench
- This double end pencil contains eyebrow color on one end and a screw brush applicator on the other end.
- By means of revamping double end seals washing system, damage of mechamical seal was decreased and operation life of pump was increased.
- An introduction is given about structure, specifications and features of double end wood flooring profilers and laminate flooringp rofilers.
- By equipment modification, process selection and optimization, double end spinning was achieved on the present PET FDY spining line. And the economic benefit was obtained.