9 Parts and accessories of scientific apparatus and nautical, surveying, electric, photographic, optical, weighing, measuring, signaling and monitoring instruments, automatic and recording apparatus, and calculators, namely, digital position indicators, levelling instruments, magnets, level indicators, flow indicators, level indicators, mechanical and electronic, analog and digital position indicators for machines, digital position indicators, levelling instruments, tripod supports for mechanical, electrical and electronic devices; all of the aforesaid being made of synthetic plastic materials such as synthetic resins, gum and substitutes therefor