| 摘要 |
PCT No. PCT/SE92/00240 Sec. 371 Date Oct. 5, 1993 Sec. 102(e) Date Oct. 5, 1993 PCT Filed Dec. 16, 1993 PCT Pub. No. WO92/18076 PCT Pub. Date Oct. 29, 1992Hearing-protector plug made of plug material in which there is distributed a detectable material in powder form, particularly iron powder. If lost, such as in the food industry, the plug can be traced with the aid of detection equipment. |
