The supplier of a soil-sifting machine in which a 17-year-old Bristol teenager became trapped and died, told a jury the device was properly manufactured and designed.

Philip Shakesheft, a director of Portable Conveyors Ltd, told Bristol Crown Court on Monday that he liaised with Roy Hill of R E Hill & Son in Dundry, for the supply of the secondhand soil sifter to replace a similar machine destroyed by fire.

Mr Shakesheft said the machine he supplied for £17,000 plus VAT, which claimed the life of teenager Lee Mason in April 2007, was properly refurbished.

Farm owner Roy Hill, aged 66, and his son Michael, 32, both deny manslaughter by gross negligence.

The pair also deny breaching health and safety rules, but Roy Hill has admitted a separate health and safety charge in employing Lee without carrying out a risk assessment.

A jury has heard Lee, a trainee ground worker, was left in sole charge of the device and without a safety guard in place, became trapped and was pulled towards the framework, crushing his neck.

Mr Shakesheft said: "He was looking for an identical replacement.

"The equipment we had, had to be built up to the same specification as the original machine."

Mr Shakesheft said specifications were done and the machine was delivered in February 2007.

He said R E Hill & Son reported problems with soil spilling but a fitter from Portable Conveyors Ltd went and remedied the problem.

Mr Shakesheft said the machine had guards which had to be removed when components were greased.

He did say that later the Health & Safety executive pointed out to his company that two guards on the machine should be upgraded to meet safety regulations and also it was pointed out that a conveyor belt should be adjusted externally rather than internally.

The case continues at Bristol Crown Court.