Math geek Pi symbol, blue on black Keychain

It you would like to get the design where the first 10,000 numbers of Pi are clearly visible, I also have that design, with a few variations, on my store. Pi is an irrational number, that is calculated by dividing the circumference of a circle by its diameter. Nothing seems so simple, yet Pi is one of the most fascinating, non-repeating numbers (at least for now) ever. Show of your love for mathematics with this design, full of geeky attitude.