The assembly is very straight forward , just a bolt and a plastic insert, but.......the bolt uses an L- wrench(supplied) that inserts into a very minimal depth site not sufficient to maintain
the torque required to tighten the nut to the bolt.Too technical? not really; went and bought std. hex nut bolt and now have two great chairs.
They need to vet the bolt supplied; make it simple and friendly to the puchaser.