There seems to be a lot of the synth opiates around now - when you look at the active dose range then they can be extremely dangerous if not handled with care. Scales are really not an option either.
Hi and welcome, as Bearlove said you gotta pay attention with U-47700, it's really potent and addictive.
Also the high is very shortlived so you'll find yourself redosing every few hours to not get into withdrawals.