Dwarf White Isopods (Trichorhina tomentosa) are sold in packs of 50 or 200. Excellent clean up crew and great for seeding dart frog tanks, supplemental food and eating waste. We will ship via USPS Priority mail, please check temperatures before ordering. We will always work with you on order issues, but if the temperature will be below 20 and above 90 please let us know to hold your order for better temps. Thanks!