  In this short research note we obtain double definite integral expressions
for the Kapteyn type series built by Kummer's $M$ (or confluent hypergeometric
${}_1F_1$) functions. These kind of series unify in natural way the similar
fashion results for Neumann-, Schl\"omilch- and Kapteyn-Bessel series recently
established by Pog\'any, S\"uli, Baricz and Jankov Ma\v{s}irevi\'c.
