Patients having radiotherapy to their head and neck wear an immobilisation shell to prevent patient movement and improve treatment accuracy. These shells tend to cover the face and have the potential to cause anxiety and distress in patients, particularly if they suffer with claustrophobia or a similar fear. The study will use an 'open-face' shell that does not cover the face and compare this with the investigators' current 'closed-face' shell. The investigators will obtain treatment verification x-ray images to assess the daily set-up errors and compare these between the two shell type, and ask both patients and radiographers of their experiences from using the shells.