Grounded 120V 6oHz Analog (mechanical) timer with non-removable on-off pins for up to 48 on-off cycles per 24-hr period. This tested timer works fine but has a slight humming sound that may not be important to you. Most mechanical timers emit some slight buzzing sound which may be more noticeable in some than others. Most ultimately do. This AS-IS pricing includes shipping and is NON-EXCHANGE/RETURNABLE/REFUNDABLE.