brake valve spool 制动阀阀芯

brake spool 制动器滑阀

brake control spool 制动器操纵滑阀

brake reducing spool 制动器减压滑阀

brake spool assembly 制动器滑阀总成

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

secondary brake valve spool 辅助制动阀滑阀