BT1000AV CONTROL VALVE Parts group BT1000AV B20002 CONTROL VALVE B21002 CONTROL VALVE (COMPONENT PARTS) B21202 SWING SPOOL SECTION [COMPONENT PARTS] B21302 BOOM SPOOL SECTION [COMPONENT PARTS] B21502 STABILIZER SPOOL SECTION [COMPONENT PARTS B21602 DIPPERSTICK SPOOL SECTION [COMPONENT PART B21702 BUCKET SPOOL SECTION [COMPONENT PARTS] B21900 OPTION SPOOL SECTION [COMPONENT PARTS] sale parts diagram catalog online construction equipment excavator tractor