NOT TTC but ? about OV kits

is there some sort of ov kit that comes 5-7 in a pack but you only use one a month my friend said she was just looking and she said she saw a kit for $30 that has pee sticks and you only use one a month so you pee on a stick and it tells you when you will be fertile. i told her i was almost Positive for $30 you get the basic 7 days ovualtion kit but she swears im wrong. i think she is mistaking this for the clear blue fertility monitor. any inout greatly appreciated.
TIA

maybe she just say the test sticks for the monitor and did not know you had to shell out more $$ first?