Hosetail connections make this relatively easy to attach, although I had some problems because the size of my pipe did not correspond with the horsetails, a problem I was able to overcome through the use of waterproof tape.
Once attached, the valve is working reasonably well, although because I was not able to insert it in the optimum position, it does allow air back into the pipe.
Self assemble on arrival. The material appears to be quite brittle but as long as you treat it with the respect it deserves it goes together and works perfectly. Far more value for money than others out there. Add a little Vaseline to keep things running and fitting even better. Job done!