Otherwise known as a Flow-Span. Are you repairing PVC or Poly?
PVC-----Flow-Span
Poly-----Couplers, Pipe, and clamps
Should mention that Flow-span's are tricky to use if the pipe being fixed is curving and not in a straight line.
Another method is to use 2, 45 degree elbows if the pipes don't line up exactly even or straight.