C&T Auctioneers will offer a selection of rare British second world war spy gadgets in its July 11-12 sale in Tunbridge Wells.

All were developed by the Special Operations Executive (SOE), the top-secret organisation founded to aid resistance movements and carry out acts of sabotage on Axis targets across Europe.

This concealed radio transmitter was used on the Belgian border 

One of the most intriguing gadgets is a "biscuit tin" radio transmitter. 

They're so-named as they were often crammed inside tin boxes. This one is housed in a suitcase. 

It was used on the Belgian border during the war – although the precise nature of the mission has not been revealed.

It’s valued at £1,200-1,600 ($1,545-2,060).

There’s also an incredible assassination dagger concealed inside a smoking pipe.

At seven inches long, it’s a surprisingly deadly proposition and is valued at £500-800 ($643-1,030).

The dagger is concealed in the stem of the pipe

C&T Auctioneers spokesman Mathew Tredwin said in the Mail Online: “Some of these weapons are quite chilling when you look at them now but they give you an immediacy of a kill or be killed scenario many of these agents would have faced…

"It was incredibly dangerous. If you were caught that was it, you would be executed.

“These stealth weapons are few and far between. Once they were used by the secret agents they were often disposed of.

“They are very popular because of their rarity and the romanticism surrounding the secret service. Everyone wants to be James Bond.”

That strength of demand could push values up on the day. 

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