"OVERLAY" MEANS 'HOW MUCH THE CABINET FRAMEWILL BECOVERED'. EACH DIFFERENT CONCEALED HINGE WILL FORCE THE DOOR TO COVER DIFFERENT AMOUNTS OF THE FRAME ON THE FRONT OF THE CABINET, ALSO CALLED THE "FACE FRAME".

A "900C" HINGE IS A 1/2" OVERLAY HINGE, SO THAT HINGE WILL FORCE THE DOOR TO COVER 1/2" OF THE CABINET FACE FRAME (on the hinge side). TO KEEP THINGS SYMMETRICAL, YOU SHOULD USUALLY ADD 1/2" TO THE HANDLE SIDE OF THE DOOR ALSO.
SO, BY MAKING THE DOOR 1" WIDER THAN THE CABINET OPENING, THE DOOR WILL 'OVERLAY' 1/2" ON THE HINGE SIDE AND 1/2" ON THE HANDLE SIDE WHEN USING THE "900C"(1/2" OVERLAY) HINGE.

IF YOU WOULD LIKE TO COVER MORE OF THE CABINET FRAME,YOU CAN ORDER A 3/4" OVERLAY HINGE, AND MAKE THE DOOR 1 1/2" BIGGER THAN THE OPENING SIZE.

REMEMBER, IF YOU WANT MORE 'OVERLAY' (COVERAGE OF THE FRONT FRAME), YOU NEED TO DO TWO THINGS:
1) USE A LARGER 'OVERLAY' HINGE...
2) MAKE THE DOOR WIDER. BY DOUBLING THE 'OVERLAY' OF THE HINGE, THE DOOR WILL COVER THE FRAME EVENLY ON BOTH SIDES.

THE "900V" HINGE WILL FORCE THE HINGED SIDE OF THE DOOR TO COVER THE FRAME BY 1 1/2" ON THE HINGE SIDE, SO THE DOOR WOULD LIKELY NEED TO BE MADE 3" BIGGER THAN THE OPENING TO KEEP IT SYMMETRICAL. YOU'LL WANT TO STAY AWAY FROM THESE HINGES UNLESS YOU COMPLETELY UNDERSTAND HOW THEY WORK, AND HOW MUCH OF THE FRAME THEY WILL ACTUALLY FORCE THE DOOR TO COVER.

HOW TO MEASURE THE 'OVERLAY' OF YOUR EXISTING DOOR:
(In this instance, we are measuring the overlay on a door with "900V" hinges)