Abstract: A cooling device for a drilling tool to be used in a wellbore, comprising an inner sleeve that forms a central void, an outer sleeve concentric with the inner sleeve and aligned along a same axis as the inner sleeve, creating a first annular space between the inner sleeve and the outer sleeve, and at least one thermoelectric cooler, comprising a hot-side and a cold side, positioned in the annular space, wherein the central void is at least partially filled with instrumentation, and the at least one thermoelectric cooler prevents the instrumentation from attaining a predetermined temperature set-point.