Abstract: The invention relates to a biocompatible, low-viscous, radiation curab]e formulation, particularly for use in stereolithography, for use in medical technology, in particular, for producing earpieces, containing: a) 55-95 % by weight of a monomeric or oligomeric dimethacrylate based on bisphenol A or bisphenol F; b) 0-20 % by weight of a urethane methacrylate having a functionality of n<4 and a viscosity<15 Pa s; c) 2-15 % by weight of a monomeric aliphatic or cycloaliphatic dimethacrylate having a viscosity<5 Pa s; d) 0-15 % by weight of a monofunctional methacrylate having a viscosity<3 Pa s; e) 0.5-6 % by weight of a photoinitiator or a combination of a number of photoinitiators whose absorption is located within the wavelength range of the laser beam used; f) 0.