knob 30 adjusts the angle of lamp 26 so that it is at the eye level of a driver within a vehicle approaching from the rear notwithstanding the angle of the rear window upon which the housing is mounted as illustrated in fig2 frame 22 may have an adhesive tape 46 supported within its confines so that frame 22 may be secured adhesively to the inside of an automobile rear window rotatable inner housing 24 may then be adjusted to set the lamp 26 at the proper angle for maximum effect as illustrated in fig3 adjusting knob 30 may include a vertical indexing feature 45 so as to display the angle of adjustment of inner housing 24 and lamp 26 knob 30 includes an inwardly axially extending hub 37 with a radially extending cap or lug 38 which complementally engages corresponding concavity 60 within inner housing 24 end knob 30 exterior is seated within peripheral bead 36 defined at the end of the outer housing as illustrated in fig1 the indexing feature may be in the form of an insertable tab 58 at the other end of housing 20 knob 32 is seated within peripheral bead 33 at either end of inner housing 24 a circular bead 40 abuts the inside surface of the outer housing wall as illustrated in fig1 knob 32 inner end 37 may be snap fitted against the end wall of the inner housing so that there is a.