Bullet_point: ['All components plug into each other. No hard wiring required. 32ft Cable from speaker to sensor', 'No hard wiring required, all components plug into each other', 'Perfect for monitoring an entrance or for use as an entrance indicator', 'Perfect for monitoring an entrance or use as an entrance indicator', 'Photoelectric beam sensor; Two tone choices - siren and "ding dong"', 'Retro-Reflective Alert System comes with the following: NIR retro-reflective sensor, reflector, Speaker, 9VDC 200mA power adapter. 6ft cable', 'Retro-reflective design', 'Save when you buy the 2-Pack!', 'Speaker volume can be adjusted or turned off; When in siren mode, sounding time is adjustable from 3 to 30 sec', 'Standalone system includes reflector, adapter, sensor and chime', 'Will make "ding-dong" sound or siren sound when the beam is interrupted'] (Page 1)