7 - lead in high melting temperature type solders (i.e.lead-based alloys containing 85 % by weight or more lead)
- lead in solders for servers,storage and storage array systems,network infrastructure equipment for switching,signalling,transmission as well as network management for telecommunications
- lead in electronic ceramic parts (e.g.piezoelectronic devices).
含铅超过85%的高熔点焊锡.内部都是这个
TO220钎焊丝也是含铅92.5%的焊锡.