A set of mechanical stumps used in the run up to an Ashes tour so controversial that it led to diplomatic unrest have been put up for auction.

The notorious series of 1932/33 became known as the Bodyline tour and remains a dark moment in English cricket history.

Stumps that England's fast bowlers may have practised on during their 31-day passage to Australia are to sold at a Norwich auctioneers.

The stumps were made 10cm higher than regulation size and came with a built in unit at the base which indicated how hard the ball had been bowled.

A set of mechanical stumps that may have been used in the run-up to the most controversial Ashes series ever have been put up for auction. The notorious series of 1932/33 became known as the Bodyline tour after the dangerous tactics English cricketers used in the Tests

The mechanical contraption allowed the stumps to tilt backwards upon impact and reveal the force of the delivery, ranging from one to six.

The series became so controversial because of England's aggressive tactics.

Facing the fearsome batting of Australian legend Don Bradman, they were accused of devising a means of neutralising the run-sensation that undermined the gentlemanly conduct of the game.

England's men bowled hard and fast down the line so that the ball would bounce up at their opposition batsman's face.

The receiving batsman, faced with three options could duck out of the way and expose their wicket, play the ball but risk being caught out by nearby fielders, or move in and risk the agonizing impact of the fast ball.

Australia accused the English cricketers of unfair play and ungentlemanly conduct - slurs so offensive that it spilled into the diplomatic arena with prime ministers of both countries intervening.

Now these stumps, inscribed with the words 'tour 1933' are set to sell for a guide price of £350 at Knights Sporting Auctions in Norwich.

The Bodyline tactic, also known as fast leg theory, meant bowling the ball hard and fast down the line. The ball would bounce up high towards the opposition's face compelling them to either move out of the way and expose their wicket, or take the full impact to the head

Harold Larwood (pictured) was one of England's most fearsome bowlers known for his speed and accuracy. He was one of the key implementer's of the aggressive fast leg theory

Douglas Jardine, captain of the Marylebone Cricket Club - cricket's then governing body - came under intense scrutiny for his fearsome Bodyline tactics, also called fast leg theory.

Even some of Jardine's teammates refused to go along with the strategy that endangered their opponents.

The set of stumps he used to practice on, called Pullen's Auto Cricket, were patented in 1934 by J.G.S Pullen of Kent but were never developed further.

England returned home as heroes having won the series 4-1.

However the Australian cricket authorities lodged a formal complaint to the MCC in London over their 'unsportsmanlike tactics' - a criticism that remains at the heart of English cricket's most controversial moment.