Check the listing for details. ALARM SYSTEM KEY SWITCH (ROUND KEY) MAINTAINED, 2-KEYS, SPST 4AMP@125, ON & OFF. Color: Silver, Condition: New. Listed at 11.55 USD. ALARM KEY SWITCH (MAINTAINED). KEY PULLS IN TWO-POSITIONS: ON & OFF. PROFESSIONALLY MADE. DOUBLE-D MOUNTING HOLE. COMPLETE WITH TWO ROUND-KEYS, KEY RING, TERMINAL SCREWS, TWO INTERNAL TOOTH WASHERS, TWO CRIMP-TYPE WIRE RING CONNECTORS AND CYLINDER RETAINING NUT. FACTORY-NEW. QUANTITY꞉ ONE medium-security, tubular-key key switch, two tubular keys and two crimp-on ring connectors. Maintained operation. Key removes in both on and off positions. SPECIFICATIONS꞉ This switch is rated for 4-amps at 125 VAC / 2-amps at 250 VAC (so if you are going to use it to control higher voltages/higher amperage, you will need to incorporate a relay into your circuit). The housing is triple-plated. NAMA Standard 3/4” mounting hole with two “flat sides” (AKA “double-D”). Contact resistance is 10mΩ maximum. The insulation resistance is 500 MΩ minimum. The dielectric strength is rated at 1500 VAC, one-minute. They keys are round, seven-pin keys. This key switch is typically used with security systems / alarm panels (although it can be used for many other applications). The "contact" configuration for this key switch is SPST and wire attachment is by screw terminal attachment at the rear of the switch. In fact, we've even thrown in two crimp-style wire “ring connectors” to save you a trip to the store. This key switch is not spring loaded (i.e. it is not momentary, it is maintained). The key will come out in two positions: ON and OFF. The key rotates approximately 90-degrees. Mounting is by the included retaining nut. This key switch mounts in the industry-standard single-D or double-D 3/4" hole. DIMENSIONS and WEIGHT꞉ The key switch measures approximately 2.05" from the lock's face to the end of the screw tabs. The threaded cylinder measures 0.73" across at its widest, the threaded cylinder measures 0.655" across between the flat sides. The face measures 0.84" across and the retaining nut measures 0.86" across between its flat sides. The key switch, keys, key ring, ring connectors and retaining nut weigh 2.5 ounces (72 grams). Please see the dimensions in the listing's photos. Again, this is a large key switch, NOT one of those tiny key switches out of Asia that will only handle a couple hundred milliamps. KEY SWITCH USES꞉ Use this key switch to shunt-out (bypass) doors or zones on your alarm system; shunt in or out your barn, shed, garage, or outbuilding to your home's security system; to disable electronics such as the keyboard to your computer; to enable/disable an outside push button to your garage door (granting access to your children, friends, or "domestics" only when necessary); to restrict access to building automation features; use it to control a relay (to turn on/off lights, motors, electrical devices, power tools in your shop, etc.). CONDITION꞉ Factory new. SHIPPING COST꞉ Your shipping cost is calculated upon checking out. To keep your shipping cost as low as possible, it's calculated based on weight, package size and destination (i.e. “DIM”). This item ships by USPS First Class or Priority Mail. Orders typically ship within one business day of your payment being received.