Our collar has a breakaway system (punctured hole to make the system more fragile) designed to break under the strength of a struggling 4.5 lbs cat and prevent strangulation, which corresponds to a 120 Newton force and which is sufficient in nearly all circumstances.  To date, we have shipped millions of cat collars and fortunately, not one incidence of accident has been reported.  Although we are able to produce a weaker breakaway collar, we are convinced consumers would prefer the current design since the weaker style will on occasion break too easily and be at risk of breaking even as the collar is fitted on the cat.