Hastings loupe with compound lens with a high optical throughput and with a lens system that consists of three individual lenses. The lenses of this A.KRÜSS loupe are achromatic (color-corrected) and aplanatic (distortion-free). Their special design eliminates the visible colour flaws, and the magnification is extremely high-contrasted and provides images that are razor-sharp up to the edges. Useful helper and indispensable for basic gemmological equipment.