brake spool assembly 制动器滑阀总成

brake valve spool 制动阀阀芯

brake control spool 制动器操纵滑阀

brake reducing spool 制动器减压滑阀

left brake selector spool 左侧制动器选择器柱塞

parking brake valve spool 停放制动器阀滑阀

brake control valve spool 制动器控制阀阀芯

spool brake 滑阀制动器

secondary brake valve spool 辅助制动阀滑阀