opening 66 of conversion assembly housing 62 when connecting attachment module 120 to the rest of conversion assembly 60 and its housing 62 an attachment interface 68 made of rubber or a similar material is included between them the posterior of conversion assembly housing cavity 64 holds driver module 70 and power module 80 as well as contact unit 100 which includes a body coupling 101 and a support plate 102 contact unit 100 is used to provide electrical contacts between driver module 70 power module 80 and control module 90 contact unit 100 connects batteries of power module 80 to driver unit 70 when the sensor detects use of the facility referring to fig3 9 and 9 a contact unit 100 includes a body coupling 101 a support plate 102 and a set of electrical contacts 103 a and b 108 a and b 106 the driver module body 72 pivots about hinges 74 a and b driver module body 72 includes a contact arm 76 which interfaces with contact unit 100 for setting off conversion unit 60 when use of the facility is sensed optical module 90 includes an enclosure cover 92 an optical window 94 and an upper enclosure surface 96 and is held within the anterior portion of conversion assembly housing cavity 64 enclosed by an anterior.