I am installing an under-the-sink water filtration system, and cannot get the water shut-off valve to budge at all. Tried WD-40. Can I use a self piercing saddle valve, instead, so that I don't have to wrestle with this?

I am installing an under-the-sink water filtration system, and cannot get the water shut-off valve to budge at all. Tried WD-40. Can I use a self piercing saddle valve, instead, so that I don't have to wrestle with this?

If this is a angle stop,(see image) put a pair of pliers on the handle for leverage and turn the handle clockwise to close the valve. Once you get the thing to turn you can finish by hand. Good luck, Tom

I do not like Saddle Valves. I don't remember the last time I actually installed one. But, yes, you could use it if you don't want to mess with frozen angle stop.