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The sign accompanying the engine. It reads

RL-10 Engine

Pratt & Whitney developed the RL-10 engine in 1959. Since the first successful RL-10 powered Centaur rocket flight in 1963, more than 175 RL-10s have operated in space without a failure.

Thrust:	6,500 lb
Fuel/Oxidizer:	Liquid hydrogen/liquid oxygen
Mixture Ratio:	5:1
Specific impulse:	444.4 sec

This is a rather old sign; Pratt & Whitney issued a press release in April of 2009 marking the launch of the 400th RL-10 engine.