text: Commission and published on the website indicated below, applicable on the day when it 
  issues the payment order. 
  
  The contractor makes any conversion between the euro and another currency at the 
  monthly accounting exchange rate, established by the Commission and published on the 
  website indicated below, applicable on the date of the invoice. 
  
  http://ec.europa.eu/budget/contracts_grants/info_contracts/inforeuro/inforeuro_en.cfm 
  
  **II.21.4. Costs of transfer**
  
  The costs of the transfer are borne as follows: 
  
  (a) the contracting authority bears the costs of dispatch charged by its bank; 
  (b) the contractor bears the costs of receipt charged by its bank; 
  (c) the party causing repetition of the transfer bears the costs for repeated transfer. 
  
  II.21.5. Pre-financing, performance and money retention guarantees 
  
  If, as provided for in Article I.6*,*a financial guarantee is required for the payment of pre- 
  financing, as performance guarantee or as retention money guarantee, it must fulfil the 
  following conditions: 
  
  (a) the financial guarantee is provided by a bank or a financial institution approved by 
  the contracting authority or, at the request of the contractor and with the 
  agreement of the contracting authority, by a third party; and 
  
  (b) the guarantee shall have the effect of making the bank or financial institution or the 
  third party provide irrevocable collateral security, or stand as first-call guarantor of 
  the contractor's obligations without requiring that the contracting authority has 
  recourse against the principal debtor (the contractor). 