What are those 'whiskers' on my cat's front legs?

I think they are ther to help them feel movement in prey they catch as they can’t see very well at close distances,

The are whiskers. Same as the ones on the cheeks, above the eyes, and a few other places on the cat’s body. For whiskers [aka vibrissae], read “feelers”—these bits of long wirey hair help cats gauge their distance from things, the one s on the head, whether they can fit through a space, the ones on the feet for prey as @lucillelucillelucille says.
All you ever want to know about whiskers here

Thank you both, @lucillelucillelucille and @anartist!
So fast and clear an answer…., wow!
<< Reading whisker-wiki right now.

@rebbel – Ooooops…there!