Use
Side road lignting, M.O.T. Group 'B' roads, mounting height 13-18 ft, road widths 30-40 ft.

Lamps
Z8495 60-200W B.C. Osram Pearl or 'Silver-light' lamps.
Z8496 80 or 125W Osram/MBF/U colour-corrected or MB/U mercury lamps.

Mounting
Side entry - The lantern requires 2.7/8 in of horizontal unthreaded 1 in B.S.P. When fully home two 1/4 in diameter Allen-type grub screws grip the barrel.

Lantern Body
Die-cast aluminium alloy. The body carries the lampholder, terminal block and cable cleat. The terminal block is wired to the lampholder by double asbestos covered heat resisting insulated wiring. An earthing screw is provided. The refractor is secured in a die-cast ring of the same material as the body and is fastened to the main casting by a hinge and quick release toggle catch, both of stainless steel. The toggle has a safety device so that two distinct actions are necessary before the refractor in its ring swings free. A topicalised felt gasket is fitted in the lower rim of the lantern body, and when the lantern is closed this makes a weatherproof joint with the hinged ring.

Lampholder
The lampholder can be porcelain B.C. or E.S. for tungsten lamps or porcelain 3-slot B.C. for mercury discharge lamps.

Optical System
The pressed prismatic refractor bowl (Z6638) is made of special glass of a white colour, giving a most pleasant appearance. The refractor has been designed to give the ideal distribution for 'Group B' roads from 'Osram' colour-corrected mercury lamps, but a similar effect will be obtained from 'Osram' Silverlight tungsten lamps. The lantern is also suitable for uncorrected mercury lamps or plain pearl lamps. An unbreakable Polycarbonate bowl Z6808 is also available.

Weathering Finish
The metals used are specially selected for their resistance to corrosion. Further protection is obtained by the use of a special one-coat self-etching heavy-bodied aluminium stove enamel on the lantern body and retaining ring.

The Z8495 lantern with the refractor bowl lowered showing the lamp and general construction.

The iso-candela diagram is based on an average lamp light output through life from 125W Osram mercury type MBF/U lamp (4,600 lumens average).

Directional intensity ratio: 2.2:1
Light above horizontal: 8%
Light output ratio: 70%
Lumens in the lower hemisphere: 2,960

Light distribution data are given for the guidance of the lighting engineer, and represent the average results of laboratory tests on a number of lanterns taken at random from stock. The data are based on the lamp characteristics stated; if the latest lamp efficiency is different, the candela or lumen values should be calculated in direct proportion to the relative lamp lumens.

Lantern weight: 7½lb (3.4 kg).