These beads are used for wrathful practices to ward away danger and for protection. These beads are NOTsmooth they are rough and there are the traditional 108 beads to count mantra or prayers on them.once you have rolled all of the besds between your fingers one bead for one time saying the prayers you count only 100 as it is believed you will make approximately 8 mistakes for every 100 recitations of the prayer. Also youalways use your left hand and you always flip the mala around once you get to the Mana bead (the last bead with the knot) that way the prayers are trapped in the beads. 

Buddhist Raksha Prayer beads