The idea behind this product is very good and it is what you pay for - it greatly offsets the cost of replacing the valve stem in the shop. . I thought it was worth every dollar. I used liquid soap to insert the extractor and had to pull quite hard to pull the stem out (although there might be a trick to make it easier to pull out) but inserting the new valve (also with some liquid soap) went very smooth. I had just changed all the tires on my Jeep Grand Cherokee Laredo (yes the tool worked really well on these types of rims, see pics if you're interested) and one of the valves was leaking. I took the car back to the shop with a valve complaint and they replaced one tire with another! I said "enough" I got this tool and did it myself - the valve I removed looked old (should have been new) which was the reason for the slow leak (see soapy water foam on the first one photo, this was about 3 psi in 4-5 days, the second picture shows the old valve after removal, and the third picture shows the new valve installed (which does not produce foam despite the large amount of soapy water). Somehow I feel like I've learned a valuable skill and I wouldn't hesitate to tackle the valve stems again, the swap itself takes a minute or two but there's quite a lot of work before and after (jacking up the car , blow a tire, inflate a tire, etc.) etc.), good luck homemade.