An end-face sealing fluidic connector for fluidic connection of fluidic modules in a microreactor, particularly fluidic connection of glass, glass-ceramic and/or ceramic fluidic modules in a microreactor, the connector comprising: a connector body having a fluid passage extending therethrough from a circular first end face, the first end face having a recess for retaining one or more O-rings, the connector body having a first end section having a circular cylindrical outer surface having a diameter in the range of from 3 to 25 mm extending along the connector body from the first end face, the outer surface of the first end section having a circumferential recess dividing the first end section into a proximal portion adjacent the first end face and a distal portion separated from the proximal portion by the circumferential recess, the fluid passage within the first end section centered within the diameter and having a diameter in the range of from 1 to 5 mm, the body having a wall thickness at the first end section within the range of from 0.8 to 10 mm; a retaining ring seated in the circumferential recess and having an inner diameter and an outer diameter; a circular cylindrical circumferential reinforcing and/or protecting ring surrounding the proximal portion of the first end section, the ring having an inner diameter equal to or greater than the diameter such that it may be easily fitted over the cylindrical outer surface of the proximal portion of the first end section and a wall thickness in the range of from 1 to 8 mm and an axial length in the range of from 2 to 15 mm, the ring comprised of a high-compression-strength polymer; and a circular cylindrical sleeve surrounding the first end section and the reinforcing and/or protecting ring, the sleeve including (a) a proximal inside surface having an inner diameter equal to or greater than the outer diameter of the ring and (b) a distal inside surface having an inner diameter equal to or greater than the diameter of the outer surface of the first end section and less than an outer diameter of the retaining ring and (c) a circumferentially extending inside bearing surface extending between the proximal and distal inside surfaces [60, 62] for engaging the retaining ring on the distal side thereof, the circular cylindrical sleeve further comprising an external thread on a proximal outer surface thereof and a gripping surface on a distal outer surface thereof. a connector body having a fluid passage extending therethrough from a circular first end face, the first end face having a recess for retaining one or more O-rings, the connector body having a first end section having a circular cylindrical outer surface having a diameter in the range of from 3 to 25 mm extending along the connector body from the first end face, the outer surface of the first end section having a circumferential recess dividing the first end section into a proximal portion adjacent the first end face and a distal portion separated from the proximal portion by the circumferential recess, the fluid passage within the first end section centered within the diameter and having a diameter in the range of from 1 to 5 mm, the body having a wall thickness at the first end section within the range of from 0.8 to 10 mm; a retaining ring seated in the circumferential recess and having an inner diameter and an outer diameter; a circular cylindrical circumferential reinforcing and/or protecting ring surrounding the proximal portion of the first end section, the ring having an inner diameter equal to or greater than the diameter such that it may be easily fitted over the cylindrical outer surface of the proximal portion of the first end section and a wall thickness in the range of from 1 to 8 mm and an axial length in the range of from 2 to 15 mm, the ring comprised of a high-compression-strength polymer; and a circular cylindrical sleeve surrounding the first end section and the reinforcing and/or protecting ring, the sleeve including (a) a proximal inside surface having an inner diameter equal to or greater than the outer diameter of the ring and (b) a distal inside surface having an inner diameter equal to or greater than the diameter of the outer surface of the first end section and less than an outer diameter of the retaining ring and (c) a circumferentially extending inside bearing surface extending between the proximal and distal inside surfaces [60, 62] for engaging the retaining ring on the distal side thereof, the circular cylindrical sleeve further comprising an external thread on a proximal outer surface thereof and a gripping surface on a distal outer surface thereof.