all about anal beads
Anal beads, also known as 'thai beads', are a string of beads designed for anal penetration. Instead of being about pressure or fullness, anal beads play on the sensation of the two ringed sphincter muscles, such that when you pull the beads out (which you do gently, with lots of lube) they pass along the muscles and create a sensation some people find very pleasing. Some sex manuals will describe anal beads being pulled out at the point of orgasm, but this isn't necessary for them to be enjoyable.
Anal beads may be connected by a string or a solid piece of rubber that has a series of balls or beads running up it.