'There are now 6 versions of the shoes, each has different modifications and some you can make yourself.
- An audible alarm system, which makes an incredibly loud noise and can be set off by hitting one shoe against the other
- A GPS system for tracking the wearer’s location
-Secret compartments for holding keys, money, condoms
- Video screens for advertising
These modifications evolved out of interviews and discussions with current and former sex workers. People didn’t want knives or guns or mace for example, because those things routinely get used against them; instead they just wanted something that would make a really loud noise. The secret compartments are because they get robbed, and can’t go to the police for help; this way they can at least get home and back into their house.'