The 2018 South African Inventions theme is Computed Tomography (CT), invented by Allan McLeod Cormack. The CT is an imaging procedure that uses special x-ray equipment to create detailed pictures or scans of areas inside the body. It is also termed computerised tomography and computerised axial tomography (CAT).
The ‘South African inventions’ theme was launched in 2016, to highlight globally relevant inventions and firsts by South Africans. The dolos was the first invention to be featured, followed by the first successful human-to-human heart transplant in 2017.
 
The reverse of the 2½ c tickey shows the different layers and tissue densities that can be distinguished with a CT scan, the denomination, and ‘AMC’ for Allan McLeod Cormack.