mr 44 non-contact measuring principle length measuring device based on non-contact principle for production monitoring in fully automatic, unsupervised production. the probe temperature is kept constant. mr 33 measuring p......mr 44 non-contact measuring principle length measuring device based on non-contact principle for production monitoring in fully automatic, unsupervised production. the probe temperature is kept constant. mr 33 measuring principle scanning function tactile length measuring device for production monitoring in fully automatic, unsupervised production. direct contact probe with high quality potentiometer (12 mm stroke).