spark plug socket for brushcutters fs 160 180 cut-off saw ts spring-loaded coupling stihl original part no.: 017705 original part no.: 11284051000 stihl chain saw 009 010 011 012 017 018 020 021 023 024 026 029 034 036 038 044 048 046 046 064 066 084 ms 170 180 192 210 230 240 250 260 270 280 spring-loaded coupling r.o. 11284051000 at