When the nut is tightened, the olive is compressed between the nut and the receiving fitting; the ends of the olive are clamped around the pipe, and the middle of the olive bows away from the pipe, making the olive effectively thicker.

Compression to 8mm Hosetail (Various Sizes)
Select Copper Pipe Size
- 1/4" (6 mm)
- 5/16" (8 mm)
- 3/8" (10 mm)
- 1/2" (13 mm)
Quantity
Compression to Hosetail
The compression fitting is composed of an outer compression nut and an inner compression ring or "olive" that is typically made of brass.