Contract number: [ complete ]  Contract conditions of December 2015  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 guarantee, it must fulfil the following  conditions:  The contractor bears the cost of providing such guarantee.  Pre-financing guarantees must remain in force until the pre-financing is cleared against  interim payments or payment of the balance. Where the payment of the balance takes the  form of a debit note, the pre-financing guarantee must remain in force for three months  after the debit note is sent to the contractor. The contracting authority must release the  guarantee within the following month. Performance guarantees cover compliance with substantial contractual obligations until  the contracting authority has given its final approval for the supply. The performance  guarantee must not exceed 10 % of the total price of the contract. The contracting  authority must release the guarantee fully after final approval of the supply, as provided  for in the contract. Retention money guarantees cover full delivery of the supply in accordance with the  contract including during the contract liability period and until its final approval by the  contracting authority. The retention money guarantee must not exceed 10 % of the total  price of the contract. The contracting authority must release the guarantee after the expiry  of the contract liability period as provided for in the contract.  The contracting authority must not request a retention money guarantee where it has  requested a performance guarantee. The contractor (or leader in the case of a joint tender) must send an invoice for interim  payment, as provided for in Article I.5 or in the tender specifications. The contractor (or leader in the case of a joint tender) must send an invoice for payment of  the balance within 60 days of the end of the period of provision of the supplies, as  provided for in Article I.5 or in the tender specifications. Payment of the invoice and approval of documents does not imply recognition of the  regularity, authenticity, completeness and correctness of the declarations and information  they contain. Payment of the balance may take the form of recovery. The contracting authority may suspend the payment periods specified in Article I.6 at any  time by  notifying the contractor (or leader in the case of a joint tender) that its invoice  29  II.20.7. Suspension of the time allowed for payment  II.20.6. Interim payments and payment of the balance  (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;  (b) the guarantor stands as first-call guarantor and does not require the contracting  authority to have recourse against the principal debtor (the contractor). 