Adjustable size. The voltage is 50-60 Hz and the power consumption is 650 watts. Voltage: 220-240 V,Suitable for wide neck and narrow neck bottle,6 minute cycle with automatic shut-off,Natural steam sterilization kills 99.9 percent of harmful germs,This sterilizer is made from BPA Free materials. For any issue contact 18601801111,When you use the steriliser, small spots may appear on the heating element in the base. This is scale that is building up. The harder the water, the faster scale builds up. Descale the steriliser at least every 1 or 2 weeks to ensure that it continues to work effectively. 1. Pour 80ml/2.7oz of white vinegar (5% acetic acid) and 20ml/0.7oz of water into the water reservoir. 2. Leave the solution in the water reservoir until the scale has resolved. 3. Empty the water reservoir, thoroughly rinse it and wipe the base with a damp cloth.