system: You are a contract-analysis assistant performing a span-extraction task. You are given an excerpt from a commercial contract and the name of a clause type to locate within it.

Return the exact text of the requested clause, copied verbatim from the excerpt — identical wording and punctuation, with no paraphrasing, summarising, explanation, or added commentary.

The excerpt is one window of a much longer contract and often will not contain the requested clause. If the requested clause does not appear in this excerpt, respond with exactly: Not found.

Output only the extracted clause text, or the exact string `Not found.` — nothing else.

user: Contract excerpt:
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Exhibit 10.16 SUPPLY CONTRACT Contract No: Date: The buyer/End-User: Shenzhen LOHAS Supply Chain Management Co., Ltd. ADD: Tel No. : Fax No. : The seller: ADD: The Contract is concluded and signed by the Buyer and Seller on , in Hong Kong. 1. General provisions 1.1 This is a framework agreement, the terms and conditions are applied to all purchase orders which signed by this agreement (hereinafter referred to as the "order"). 1.2 If the provisions of the agreement are inconsistent with the order, the order shall prevail. Not stated in order content will be subject to the provisions of agreement. Any modification, supplementary, give up should been written records, only to be valid by buyers and sellers authorized representative signature and confirmation, otherwise will be deemed invalid. 2. The agreement and order 2.1 During the validity term of this agreement, The buyer entrust SHENZHEN YICHANGTAI IMPORT AND EXPORT TRADE CO., LTD or SHENZHEN LEHEYUAN TRADING CO, LTD (hereinafter referred to as the "entrusted party" or "YICHANGTAI" or "LEHEYUAN"), to purchase the products specified in this agreement from the seller in the form of orders. 2.2 The seller shall be confirmed within three working days after receipt of order. If the seller finds order is not acceptable or need to modify, should note entrusted party in two working days after receipt of the order, If the seller did not confirm orders in time or notice not accept orders or modifications, the seller is deemed to have been accepted the order. The orders become effective once the seller accepts, any party shall not unilaterally cancel the order before the two sides agreed . 2.3 If the seller puts forward amendments or not accept orders, the seller shall be in the form of a written notice to entrusted party, entrusted party accept the modified by written consent, the modified orders to be taken effect. 2.4 Seller's note, only the buyer entrust the entrusted party issued orders, the product delivery and payment has the force of law. 1 Source: LOHA CO. LTD., F-1, 12/9/2019 3. GOODS AND COUNTRY OF ORIGIN: 4. Specific order: The products quantity, unit price, specifications, delivery time and transportation, specific content shall be subject to the purchase order issued by entrusted party which is commissioned the buyer. 5. PACKING: To be packed in new strong wooden case(s) /carton(s), suitable for long distance transportation and for the change of climate, well protected against rough handling, moisture, rain, corrosion, shocks, rust, and freezing. The seller shall be liable for any damage and loss of the commodity, expenses incurred on account of improper packing, and any damage attributable to inadequate or improper protective measures taken by the seller in regard to the packing. One full set of technical All wooden material of shipping package must be treated as the requirements of Entry-Exit Inspection and Quarantine Bureau of China, by the agent whom is certified by the government where the goods is exported. And the goods must be marked with the IPPC stamps, which are certified by the government agent of Botanical-Inspection and Quarantine Bureau. 6. SHIPPING MARK: The Sellers shall mark on each package with fadeless paint the package number, gross weight, net weight, measurements and the wordings: "KEEP AWAY FROM MOISTURE","HANDLE WITH CARE" "THIS SIDE UP" etc. and the shipping mark on each package with fadeless paint. 7. DATE OF SHIPMENT: According to specific order by YICHANGTAI or LEHEYUAN. 8. PORT OF SHIPMENT: 2 Source: LOHA CO. LTD., F-1, 12/9/2019 9. PORT OF DESTINATION: SHENZHEN, GUANGDONG, CHINA 10. INSURANCE: To be covered by the Seller for 110% invoice value against All Risks and War Risk. 11. PAYMENT: Under Letter of Credit or T/T: Under the Letter of Credit: The Buyer shall open an irrevocable letter of credit with the bank within 30 days after signing the contract, in favor of the Seller, for 100% value of the total contract value. The letter of credit should state that partial shipments are allowed. The Buyer's agent agrees to pay for the goods in accordance with the actual amount of the goods shipped. 80% of the system value being shipped will be paid against the documents stipulated in Clause 12.1. The remaining 20% of the system value being shipped will be paid against the documents stipulated in Clause 12.2. The Letter of Credit shall be valid until 90 days after the latest shipment is effected. Under the T/T The trustee of the buyer remitted the goods to the seller by telegraphic transfer in batches
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Extract the exact clause related to "Effective Date" from the excerpt above.