Manufacturer Secura Key Model SK-KPM Dimensions H x W x D: 7.25 x 1.75 x .875 (18.4 x 4.50 x 2.20 cm) Operating Temperature -40 to +257 F (-40 to +125 C Programming Pressing one or more numbers followed by the # key sends the sequence of digits via 26 bit Wiegand protocol to a host control panel. Each keypress causes the Red LED to flash and the beeper to sound. Voltage Input 12-28 VDC Certifications IP68 (water and dust resistance), MIL Standard 810C, 202E, 461B, 462 U.L. Listed 2 UL & CE Warranty 2 Year Warranty Weight 2.0000