The only engineering plastic of natural origin (derived from castor oil), it is a polyamide which, unlike the other nylons, does not absorb humidity. It has all the good mechanical features of polyamides: tensile stress, compressive strength, wear resistance, etc. Moisture content does not influence its shock resistance. It has very good ageing and low temperature resistance.
Nylon 12 has all the excellent mechanical features of polyamides without their weakest point, hygroscopicity. Its higher price does however prevent wider usage.