We have recently investigated a hybridization gap in Kondo systems using HET and several papers along with a review have been published. Our study shows a universal scaling between the spin gap estimated through inelastic neutron scattering (INS) and the Kondo temperature (Fig.1). We here propose to investigate a spin gap in CeOs4As12 using MERLIN. Recent resistivity study of CeOs4As12 reveals Kondo insulator type behaviour below 100 K with a small energy gap of 6.3 meV. The susceptibility exhibits a broad maximum near 50 K, which predicts a spin gap of 13 meV in INS response using our scaling. Furthermore, the susceptibility behaviour suggests a possibility of another maximum above 300 K. It is therefore important to investigate the spin gap in CeOs4As12 using INS to confirm the presence of the spin gap and further to confirm the existence of two spin gaps as observed in CeOs4Sb12.