Electron paramagnetic resonance (EPR) was used to study high-purity semi-insulating 4H-SiC irradiated with 2 MeV electrons at room temperature. The EPR signal of the EI4 defect was found to be dominating in samples irradiated and annealed at 750 C. Additional large-splitting Si-29 hyperfine (hf) lines and also other C-13 and Si-29 hf structures were observed. Based on the observed hf structures and annealing behaviour, the complex between a negative carbon vacancy-carbon antisite pair (VCCSi-) and a distance positive carbon vacancy (V-C(+)) is tentatively proposed as a possible model for the EIO4 defect.