Customs officers have seized almost 30 kilograms of precursor drugs used to make amphetamine-type drugs such as ice in Sydney.

Officers at Sydney's international mail and air cargo facilities last week found around 17 kilograms of ContacNT, four kilograms of pseudoephedrine and 7.4 kilograms of ephedrine in 11 separate consignments from China, Hong Kong and Singapore.

The drugs were hidden in pens, ash trays, an air compressor, steel bolts, a brush roller, industrial hoses, cardboard packages, drive shafts and cameras, Customs said on Tuesday.

Customs and Border Protection's Jagtej Singh said the precursors were highly dangerous substances used for manufacturing methamphetamine.