Tognella FT 1251/2 bidirectional flow restrictor, 3/8" BSP, for in-line mounting: it controls the flow in both directions.
Tognella FT 1251/2-38 bidirectional flow restrictor, with 3/8" G threads, for in-line mounting. It holds back the oil equally in both directions and slows the cylinder or motor on both movements.
This valve has no check valve: the return does not flow freely. If only one movement needs controlling, choose the one-way FT 1251/5 version.
The same series includes 1/4" and 1/2" sizes. Check the thread and the room available for the adjustment knob.
Specific References
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