The Closed Loop System from NectarX with the size of 4 inches is ideal for extraction with N-butane gas such as from Twisted Labs. The advantage of loop systems is that the N-butane can be recycled without a large loss and can be used again for the next extraction.
For the 4 inch system, we recommend 3 bottles of Twistedlabs N-Butane with 320ml content.
After butane gas recirculation, a vacuum pump can even be connected to remove the remaining butane from the BHO.
The whole system is made of stainless steel with Teflon seals, and has a sight glass for control.
The whole system is equipped with quick couplings to make the work easier and safer, in all important places it has ball valves for closure so that no butane can escape.

We strongly recommend that you use the system in a well-ventilated place or outdoors, because butane is highly flammable.
Smoking or fire nearby can cause an explosion.

Size:
Size of the extraction tube inside: diameter 35mm, length 305mm for about 50g herbs.
Total height with attached tank: 123.5cm
Height without tank: 87cm
Tank size: Diameter outside 10cm, height outside: 19.5cm, the tank offers approx. 1L filling volume for gas