Which prong collar and size would you recommend for our dog?

I have a almost 3 year old Yorkie/Pekingese mix, he is 10 lbs and his neck is measured at 11 inches snug ( his collars are 12-14 inches to fit with comfort). He pulls on walks every single time and it's worse when he sees a dog or squirrel. We have decided to finally try a prong collar since nothing else works with him. Which prong collar and size do you recommend for him?

Thanks,
Leticia