"Features: Natural essential oil without allergy. Water resistant design. One size, adjustable for all cats. Non-allergic and odorless, safe and environmentally friendly. High efficiency and last up to 8 months. Well packaged in an aluminum storage case. To repel fleas, ticks, lice, larvae, mosquitoes, etc. Characteristics: Material: rubber + aluminum Suitable for: neck sizes up to 30 cm Item size: 35 * 1 * 0.3cm Item Weight: 11g Package Weight: 30g Package size: 8.6 * 8.6 * 2.6cm / 3.39 * 3.39 * 1.02in Package list: 1 * necklace 1 * case "