3Pcs Drip Irrigation System Automatic Self Watering Spikes Adjustable for Indoor and Outdoor Potted Plants Material: PP Product Dimensions: 17.5 x 5 cm Water Bottle Opening: 28-30 mm Quantity: 3 pieces Color: Pink Features: Easy and convenient self-watering spike that delivers a steady drip of water directly to the soil for efficient irrigation. Sturdy spike design remains securely in place once inserted into the soil. Stepless speed regulation allows control of the drip rate by adjusting the screw regulator. Compatible with water bottles that have a neck diameter of 28-30 mm, such as standard water, soda, pop, or juice bottles. Ideal for automatic watering of indoor or outdoor potted and garden plants at home or in the office, especially during vacations, holidays, or business trips. Package Includes: 3 x Self Watering Spikes Note: Please allow 2-3 cm difference due to manual measurement. Colors may vary slightly from the images due to differences in monitor displays. (1 inch = 2.54 cm)