‘Laser’ materials, as follows: (a) Synthetic crystalline ‘laser’ host material in unfinished form as follows: 1. Titanium doped sapphire; (b) Rare-earth-metal doped double-clad fibres; 1. Nominal ‘laser’ wavelength of 975 nm to 1 150 nm and having all of the following: a. Average core diameter equal to or greater than 25 μm; and b. Core ‘Numerical Aperture’ (‘NA’) less than 0,065; or Note : The item above does not apply to double-clad fibres having an inner glass cladding diameter exceeding 150 μm and not exceeding 300 μm. 2. Nominal ‘laser’ wavelength exceeding 1 530 nm and having all of the following: a. Average core diameter equal to or greater than 20 μm; and b. Core ‘NA’ less than 0,1. Technical notes: 1. For the purposes of the item above, the core ‘Numerical Aperture’ (‘NA’) is measured at the emission wavelengths of the fibre. 2. Item (b) above includes fibres assembled with end caps.