NDS Drilling Supply

NDS stocks this inline check valve with 4″ male NPT threads on both ends.  Letter A length is 6″, Letter B diameter is 4-1/2″ and Letter C diameter is 4-7/8″.  This valve is superior to the standard foot valve as it can be placed at the bottom of the mud pit.  This allows the driller to avoid placing the suction hose over the top of the mud pit.  When you place the mud hose over the top of the mud pit, you create an air bubble at the highest point of the hose arc.