These locks are silly and can be opened in seconds without a magnet. They can be brute forced easily due to the few number of combinations afforded by their design. There are only 5 digits to choose from, and a code can use a given digit only once. While there is a configuration that requires the pressing of two digits at once, I've rarely seen this used. If you assume a 3 digit code, the number of combinations to try is 5 * 4 * 3, or 60 tries. A 4 digit combination requires at most 5 * 4 * 3 * 2 tries (120). We used to have these locks in my office. After code changes i would try my hand at "breaking" into them (before reading the email containing the new code). In every case I had the lock open within 2 minutes. The hardest part was actually pressing the handle down 30-60 times.