The each push pin segments around the dial represent 15 minute periods. And there are 96 operations per day for you to set accommodates varied schedules, very convenient for precision setting. With compact design, the mechanical timer is a sort of module for DIN guide rail, which is easy to install in illumination box. The timer is adopted high-end control chip, so the timing is accurate, stable and reliable. Adopting premium anti-flame materials, the shell is solid, durable and good performance, and high temperature resistant. The length of timer is 7.5cm, the width of timer is 6cm, the height of timer is 10cm. The mechanical timer provides simple, convenient automation control for water heater, water dispenser, street lamp, staircase lamp, advertising lamp box, breed aquatics, irrigation, office power auto control, anywhere need time control in civilian, home or industrial, etc. Item Name: Mechanical Timer Material: ABS,Electronic Component Batteries: 500mAh Build-in Battery (Included) Operating Temperature: -20 - + 50 Degrees Celsius Mechanical Life: 10,000,000 Times Time Accuracy: 1s/day, +20 Degrees Celsius Contact Capacity: 16A, 250V AC Model: SUL181D Operating Time: 150H Timing Range: 24H Coil Voltage: AC 110V - 230V Electrical Life: 100,000 Times Working Reserve Time: 220VAC 200H, 110VAC 100H Minimum Setting Unit: 15 Minutes Setup Time: 96 Times Size Details: Size: 10cm x 6cm x 7.5cm/3.94" x 2.36" x 2.96" (Approx.) Notes: Due to the light and screen setting difference, the item's color may be slightly different from the pictures. Please allow slight dimension difference due to different manual measurement. Package Includes: 1 x Mechanical Timer 1 x User Manual (English)