You are buying either individual beads or complete strands

Natural Lapis Lazuli Beads Strands, Dyed, Round, Blue, 4mm, Hole: 1mm; about 44pcs/strand, 7.6"

Brow or Third Eye is the 6^th Chakra linked to mind, ideas, thoughts, dreams, psychic abilities.

Throat is the 5^th Chakra linked to communication.

Lapis Lazuli is associated with both these Chakra's.

A strand is 

Natural Lapis Lazuli Beads Strands, Dyed, Round, Blue, 4mm, Hole: 1mm; about 44pcs/strand, 7.6"