(ShareCast News) - Spectra Systems has improved its contract with a European corporate partner to secure minimum order quantities of covert materials for banknote authentication for 2016-19 and an order for $1.2m for delivery in 2015.The company, which provides technology for secure transactions, from banknotes and products to electronic gaming, said the minimum order quantities are worth around $0.7m per year, including a contracted 7% increase beginning 2016 in the price of materials.Spectra said it expects the modified contract to secure a minimum of around $6m in revenue over the four-year period.Chief executive officer, Dr. Nabil M. Lawandy, said: "This contract modification further underscores the stability of our banknote security business and also increases our margins going forward.Whilst the contract specifies minimum quantities, we would anticipate quantities equivalent to those of the prior period coupled with the benefit of the price increase."The company, which is due to release interim results late this month, said it is confident it will perform "satisfactorily" for the full year.Spectra shares were untraded on Friday.