Overfill Prevention Valve

2″ BSP Male tank fitting

Max flow – 580lpm

For Plastic and Steel Tanks Tanks

How does it Work?

Designed to act as the fill point on both metal and plastic diesel tanks.  The Filstop physically closes the inlet to the tank should the fuel level reach its maximum during delivery.  This prevents the tank from being overfilled or bursting and hence reduces the risk of pollution and expensive clean up operation that might arise from such an occurrence.


The unit for plastic tanks comes complete with fitting flange, O ring and Locking Nut (as shown in the picture) so that it can simply be fitted through a 2″ hole cut into the top of the tank. The unit for steel tanks is supplied without fitting flange, O ring nor Locking Nut (as shown in the picture) so that it screws directly into the 2″ BSP Female inlet.

Very important:  The plastic tank model requires the T Bar Fitting tool  in order to screw this in place, which is supplied as an optional extra.

Tip: For Steel Tanks, we also supply the Filstop with an undersized 2″ BSP threaded body (where the inlet thread may be not exactly 2″ BSP, as can occur on a Chinese manufactured inlet boss).  The GV4300 version must only be used where a remote filler point is being used (so that the connection to this is permanent – if the delivery driver connects direct to the GV4300-ST and his ‘delivery gun’ is worn there is a danger that this can be forced off by the back pressure caused when the internal ram valve shuts off the incoming flow of oil).

Additional Information

  • 2″ BSP spare nut available
  • Available for either plastic tanks or steel tanks
  • Fitting tool available for plastic tank model