Earlier this year I wrote about the importance of fitting blind safety cords on any roman, roller, wooden or vertical blinds in your house if you have young children. Strangulation on blind cords kills several children a year, which is particularly tragic given how cheap these safety devices are and how quick and easy they are to fit.
The cheapest ones I found were on Amazon, although I recently found out about a company which has been giving away blind safety clips for free to schools, households, businesses and charities when they have them in stock. Worth trying to get some free ones, but if they are out of stock these are the cheapest ones I found on the internet