Dimensioning enclosure cutout

[Allse]

Hello, I need to design the right size cutout for a DIN connector. There is a diagram in the datasheet (attached). Someone please tell me what size hole should I design, is it 18mm? I am not familiar with the meaning of +0.1 in the superscript or -0.1 subscript next to the dimensions and don't want to design it incorrectly as I want to have a tightly sealed connector.

[pix3l]

The +0.1mm is the tolerance. So the size can be anywhere between 18.0 and 18.1 mm. Similarly if a radius is 2.5mm -0.1 it can be anywhere between 2.4 and 2.5 mm

[Allse]

Thank you for explaining this.