Order Processing Time
All orders placed on our website are processed within 2-4 business days, from Monday to Friday, 8:00 AM – 6:00 PM Pacific Time (PT). Orders received after our daily cut-off time of 10:00 PM PT will be processed on the next business day. Please note that we do not process orders on weekends or public holidays.
Shipping Methods and Carriers
Zetlly partners exclusively with reputable shipping carriers to ensure timely delivery of your orders. We utilize:
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FedEx
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UPS
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USPS
The choice of carrier is determined by factors such as destination, weight, and delivery timeframe to provide optimal service.
Shipping Rates and Fees
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Free shipping is provided for all orders over $199.
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Orders under $199 will incur a flat-rate shipping fee of $7.99.
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All orders shipped within the United States will be subject to a sales tax charge of 5%.
Estimated Delivery Time
Once shipped, orders typically arrive within 6 to 10 business days. Our delivery times are from Monday to Friday, 8:00 AM – 6:00 PM Pacific Time (PT). Please allow additional time for deliveries to remote or rural locations.
Shipping Restrictions
Zetlly currently ships exclusively within the United States. At present, we do not offer international shipping or deliveries to P.O. boxes or APO/FPO addresses. Orders placed with addresses outside our designated delivery areas will be canceled, and refunds will be processed accordingly.
Tracking Your Order
Upon shipment, customers will receive a confirmation email containing tracking information. You can track your order directly through the provided tracking link or by visiting the carrier’s official website:
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Eligibility for Returns and Exchanges
We accept returns and exchanges within 30 days from the date your order is delivered. Items must be unused, in the original condition, and accompanied by the original packaging and receipt or proof of purchase.
How to Return or Exchange an Item
To initiate a return or exchange, please follow these steps:
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Contact our customer support at contact@zetlly.com with your order number and reason for return or exchange.
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Our team will respond within 24 hours to provide detailed instructions, including the specific Return Address for your shipment.
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Package your item securely and include all original packaging and proof of purchase.
Return shipments should be sent to: Blanq LLC 1201 South Hope Street Apt 2413, Los Angeles, CA 90015, USA
Return Conditions
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Items must be returned in their original condition, unworn, undamaged, and complete with all original packaging and documentation.
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Items returned without prior authorization or not meeting the above conditions may not qualify for a refund or exchange.
Return Shipping Costs
Customers are responsible for return shipping costs unless the return is due to our error or a defective product. We recommend using a trackable shipping service to ensure your return reaches us safely.
Non-Returnable Items
The following items cannot be returned:
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Digital products (e-books or downloadable content)
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Personalized or customized items
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Gift cards
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Zetlly accepts the following secure and widely trusted payment options:
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Stripe: Pay securely using major credit and debit cards including Visa, MasterCard, American Express, and Discover via Stripe’s encrypted payment gateway.
Payment Security
At Zetlly, your security is our utmost priority. We utilize advanced encryption technologies and robust security protocols provided by PayPal and Stripe. All payment information entered on our site is encrypted using Secure Socket Layer (SSL) technology, ensuring your financial information remains private and secure throughout the transaction process.
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Payment Process and Confirmation
Upon placing an order, your chosen payment method (PayPal or Stripe) will immediately process the transaction. You will receive an automated confirmation email shortly after your payment has been successfully completed, detailing your transaction and order summary.
Please retain this confirmation email for your records and reference in case of any inquiries or disputes.
Reverse Osmosis Systems: Design, Optimization and Troubleshooting Guide describes in depth knowledge of designing and operating reverse osmosis (RO) systems for water desalination, and covers issues which will effect the probability for the long-standing success of the application.
It also provides guidelines that will increase the performance of seawater RO desalination systems by avoiding errors in the design and operation and suggest corrective measures and troubleshooting of the problems encountered during RO operation. This book also provides guidelines for the best RO design and operational performance. In the introductory section, the book covers the history of RO along with the fundamentals, principles, transport models, and equations. Following sections cover the practical areas such as pretreatment processes, design parameters, design software programs (WAVE, IMSDesign, TORAYDS2, Lewaplus, ROAM Ver. 2.0, Winflows etc.), RO performance monitoring, normalization software programs (ROData XL and Toray Trak), troubleshooting as well as system engineering. Simplified methods to use the design software programs are also properly illustrated and the screenshots of the results, methods etc. are also given here along with a video tutorial.The final section of the book includes the frequently asked questions along with their answers. Moreover, various case studies carried out and recent developments related to RO system performance, membrane fouling, scaling, and degradation studies have been analyzed. The book also has several work out examples, which are detailed in a careful as well as simple manner that help the reader to understand and follow it properly. The information presented in some of the case studies are obtained from existing commercial RO desalination plants. These topics enable the book to become a perfect tool for engineers and plant operators/technicians, who are responsible for RO system design, operation, maintenance, and troubleshooting. With the right system design, proper operation, and maintenance program, the RO system can offer high purity water for several years.Provides guidelines for the optimum design and operational performance of reverse osmosis desalination plants Presents step-by-step procedure to design reverse osmosis system with the latest design software programs along with a video tutorial Analyzes some of the issues faced during the design and operation of the reverse osmosis desalination systems, suggest corrective measures and its troubleshooting Discusses reverse osmosis desalination pretreatment processes, design parameters, system performance monitoring, and normalization software programs Examines recent developments related to system performance, membrane fouling, and scaling studies Presents case studies related to commercial reverse osmosis desalination plants Perfect training guide for engineers and plant operators, who are responsible for reverse osmosis system design, operation and maintainance Reverse Osmosis Systems: Design, Optimization and Troubleshooting Guide is written by Syed Javaid Zaidi; Haleema Saleem and published by Elsevier (S&T). ISBNs for Reverse Osmosis Systems are 9780128241721, 0128241721 and the print ISBNs are 9780128239650, 0128239654.
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