A sheet of material is received at a sensor assembly, which includes a sensor operable to measure a property of the sheet. The inner wall is made up of a plurality of tiles having axial edges aligned generally with the direction of fluid flow, a gap being defined between axial edges of adjacent tiles. Thus, the deflector plate directs air over the inside surface of the lens to prevent fog from forming on this surface during the activity. The processor is configured to communicate, through said interface connector, via a plurality of communication protocols. Disclosed devices may comprise more than one drug, or varying concentrations of the same drug. The device comprises at least one thread guide which is arranged at a feed or drop of a circular machine for knitting hosiery or the like and has an end for dispensing a thread which laterally faces the needle cylinder proximate to its upper end, in the needle work area of the machine.