Kunti Malas are worn by the devotees of Lord Visnu for protection and purification. They are made of Tulsi (Basil) which is considered very auspicious, sacred and protective plant. The light color wood necklaces in the pictures are made of Tulsi (Basil) and the brown necklace is made of rosewood which is another sacred wood in India used for healing and to shield from negative energy.
They measure approximately 18".
Any irregularity in the beads should be deemed as normal.