Britain's most advanced attack submarine, Ambush, is due to officially join the Royal Navy fleet.
A commissioning ceremony will take place at Faslane naval base on the Clyde where the 7,400-tonne sub will officially become HMS Ambush.
The second Astute-class attack submarine was launched in January 2011 at BAE Systems shipyard in Barrow-in-Furness, Cumbria.
The nuclear-powered submarine arrived at her home port of HM Naval Base Clyde in September last year where she has undergone extensive sea trials.
Ambush is 97 metres long and holds around 100 personnel. She travels at a speed of up to 30 knots.
All seven of the Navy's Astute-class vessels will eventually be based on the Clyde.
HMS Astute entered service in August 2010.
The others are named Artful, Audacious and Anson, and two are as yet unnamed.