This product can harden in less than five minutes but fully cures in ten I love this so much and will buy more soon as there is more in stock, it has no fume smells and was safe for me to use it inside (keep the windows open for chemicals to go out though) unfortunately I mixed to much at once and hardened in my cup that I was using on my project XD so I advise to use less than half a plastic cup (the kind of party plastic ones) if you are doing a bigger project