back seating stem 是什么意思？

伊凡

·閥桿設計

/ j1 k7 q$ t( P  R0 K' l0 u采用整體鍛造工藝制成，按照標準要求確定最小直徑。
/ P3 @4 ~+ E8 s4 i
Stem Design
$ z, L* U. U  d, s; ^9 l
/ K  R' j+ D& g$ T, B* sThe stem is of integral forged design,The minimum diameter of the stem shall per the standard requirement.