Westinghouse Ceramalux/4, C250S50/DX4, deluxe High pressure sodium lamp etch.
"The indoor light with outdoor economy."
"The outdoor light with indoor color."
There’s virtually no data available for this lamp, but what follows is what little is available: Around 1978 or 1979, Westinghouse created and brought this lamp to market. (General Electric followed suit about two years later with their own version.) This lamp was the first deluxe high pressure sodium lamp. It appears that it was discontinued sometime after the Philips take over in 1983. It also appears that this lamp was not a great seller. (Philips around 1990 reintroduced the DX lamp and called it by the “Comfort” branding.) Originally only sold in the 250-watt version, a 150-watt (100V/S56), and a 200-watt version were added later.
Suggested retail price is $71.00, in 1980 dollars.