I am not quite sure what you mean by "nb", but I don't think it's a unit of length.
304.8 mm
1 in = 25.4 mm 10 in = 254 mm
1 m is 1000 mm
To convert from in to mm, multiply by 25.4. 1 in is equal to 25.4 mm 1 inch = 25.4 millimeters
10 mm
1 mm is equal to 01 mm.
1 mm is equal to 0.001 meters (m).
1 milimetre is equal to 0.001 metres.
1 mm equal 0.03936996 in. 22 mm equal 0.8661391 in.
1 dm is equal to 100 mm (as 1 dm = 10 cm 1 cm = 10 mm)
.05 mm equals 50 μm (1000 x .05).
1 METER AND 155MM EQUAL TO 1155 MM