Welcome to our store！</br>1、This product uses a high-performance dedicated microcomputer chip as the core, which can alarm bell automatically according to user settings. 2、A maximum of 20 groups in single ring mode and 40 groups in dual ring mode can be achieved in one day. 3、Accurate time and easy operation. Widely used in schools, companies, institutions to control the automatic bell. 4、Powered by 1 x AAA battery (not included), convenient for battery replacement. 5、Easy program, everyone can program it after he reads the manual just one time. <div class="wang-edit-text"><div>Condition: 100% Brand New Item Type: Microcomputer Timer Switch Material: ABS Color: As Pictures Shown Working Power: 220V / 50Hz Applicable Voltage Range: 180 - 240V Dissipated Power: Less than 5W Timing Error: Less than ± 2s / day Ring Time: 0 - 99s adjustable Double Bell Interval Time: 0 - 99 minutes adjustable Power Supply: 1 x AAA battery (not included)</div><style> .wang-edit-text{ font-family:'Arial' !important; } .wang-edit-text table { border-top: 1px solid #000; border-left: 1px solid #000; } .wang-edit-text table td, .wang-edit-text table th { border-bottom: 1px solid #000; border-right: 1px solid #000; padding: 3px 5px; } .wang-edit-text table th { text-align: center; }</style></div> <div>1 x Microcomputer Timer Switch</div><div>1 x Manual</div> Satisfaction - Our customers are our top priority. If you find any product problems after receiving the goods, such as damage and incorrect quantity of goods, please contact the seller immediately. We try our best to provide you with satisfactoryaftersalesservice</br>