These are real black lava beads bracelets, average size and stretching.
There are 2 models available. Plain which all beads are black lava. And, Stretch Chakra with lava wich has 7 different beads (stone and glass) in color that represent the chakra colors. The second model (chakras) could be some different from picture according to availability but will keep the 7 chakra colors and the lava.
The lava beads are known for their oil diffusing capability. You can use a little amount of your favorite oil or esence on your lava bracelet and will last a good time. The lava stone is made from real magma of volcanos. Its porosity and structure is perfect to hold the oil.
Chakra colors represent the opening, balancing and alignment of body chakras.
The chakra model could have some variations from picture. It will have lava and chakra beads but the chakra area and spacers might vary from picture according to beads availability. It will keep the chakra colors anyway.
The spiritual use of this stone is for spiritual protection among hard changes. Remember that the volcanos go trough hard changes and preassure so its you. And they still stand up upon transition.