Includes all taxes
The EYSDON EOS Lens to M42/M48 Adapter Ring is a professional optical conversion accessory, exclusively designed for Canon EOS EF/EF-S mount DSLR camera lenses. It seamlessly converts your Canon lens mount to standard M42x0.75mm or M48x0.75mm external thread interface, unlocking endless creative possibilities for astrophotography, optical experiments, industrial imaging and more.

Premium Core Features
Precision-Matched Canon EOS Compatibility
1:1 mold opening based on the original Canon EF/EF-S bayonet, ensuring a firm, seamless and gap-free fit without loosening, fully retaining the original optical performance of your lens, no jitter during shooting.
High-Grade Durable Material & Craftsmanship
Made of aviation-grade aluminum alloy with CNC high-precision machining, hard anodized surface treatment, excellent wear resistance, corrosion resistance and rust resistance. Lightweight and compact, it can be used stably for a long time in outdoor and complex optical environments.
Ultra-High Precision Optical Design
Strict micron-level tolerance control, accurate thread and bayonet fitting, no light leakage, no vignetting, effectively maintaining the original focus and imaging clarity, providing stable and high-quality optical performance for professional shooting.
Dual Specifications for Wide Adaptability
Two industry-standard thread specifications (M42x0.75mm / M48x0.75mm) are available, widely compatible with telescope eyepieces, filter wheels, cooled astronomical cameras, industrial cameras, monoculars and other optical equipment with corresponding thread interfaces.
Tool-Free Quick Installation & Removal
User-friendly design, no additional tools required for daily installation and disassembly. The built-in limit pin design ensures safe and stable locking, supports quick switching between different optical devices, and greatly improves your shooting efficiency.


What You Will Get
1 x EYSDON Canon EOS Lens to M42/M48 Thread Adapter Ring (Please select the correct model according to your needs)

Important Warm Tips
Flange Focal Distance Check: Before purchasing, please calculate the flange focal distance of your lens and optical equipment, and select the adapter with matching specifications. Incorrect flange distance may cause abnormal imaging, focus failure and other problems.
Professional Operation Reminder: The installation of astronomical cooled cameras and filter wheels requires professional operation. If you are not familiar with the operation, please contact our customer service for guidance to avoid equipment damage.
Compatibility Confirmation: This adapter is only compatible with Canon EOS EF/EF-S mount DSLR camera lenses, not compatible with Canon RF mount mirrorless cameras. Please confirm your lens mount before purchasing.
Maintenance Tips: Please avoid violent disassembly and installation. When not in use, store the adapter in a dry and dust-free environment, and clean the thread and bayonet regularly with a professional optical cloth.

Easy Installation Guide
Daily Basic Installation (For Telescope Eyepiece / Optical Converter)
Align the adapter's EOS bayonet with your Canon lens mount, rotate and lock it firmly.
Screw the M42/M48 thread end of the adapter into your telescope eyepiece, optical converter or other compatible equipment.
Confirm the fitting is firm, then you can start shooting or viewing.
Disassembly Steps
Press and hold the limit pin on the adapter to retract it.
Rotate the adapter along the disassembly direction, then you can easily remove it from the lens.

Professional Installation (For Astronomical Cooled Camera & Filter Wheel)
Note: Professional operation is required. Please follow the steps strictly to avoid equipment damage.
Disassemble the target plane adjustment ring of the cooled camera with a screwdriver.
Remove the back cover of the filter wheel (EFW).
Disassemble the filter wheel inside the EFW.
Tighten the screws at the interface between the EFW and the main camera.
Reinstall the filter wheel back to the EFW.
Install the EYSDON adapter ring to the EFW interface.
Install your Canon EOS lens to the adapter ring and lock it firmly.
Installation completed, you can start your astrophotography creation.

Wide Application Scenarios
Astrophotography Enthusiasts: The core accessory for astronomical shooting, perfectly matching your Canon lens with astronomical telescopes, cooled cameras, filter wheels, to capture stunning deep space, starry sky and celestial images.
Optical Research & Industrial Imaging: Ideal for industrial cameras, microscopes and optical experimental equipment, helping you achieve professional imaging effects in industrial testing, macro shooting, scientific research and other fields.
Outdoor Travel & Viewing Lovers: Ultra-lightweight and portable design, you can turn your Canon lens into a high-definition monocular with a telescope eyepiece, perfect for distant scenery viewing, bird watching, wildlife observation during travel.
Photography Hobbyists & Budget-Conscious Users: An economical and practical way to expand your optical system. No need to buy expensive professional astronomical or industrial lenses, you can unlock more shooting effects with your existing Canon lenses.


Payment Policy – BILLIONS BIRDS
At BILLIONS BIRDS, we are committed to providing a safe, secure, and seamless payment experience for our customers.
1. Accepted Payment Methods
We accept the following payment options:
Major Credit & Debit Cards (Visa, MasterCard, American Express)
Secure Online Payment Gateways (such as PayPal, Stripe, or other providers available at checkout)
Any additional payment methods displayed during checkout
All payments must be completed in full at the time of purchase.
2. Secure Transactions
All transactions are processed through encrypted and secure payment systems to protect your personal and financial information. We do not store your full payment details on our servers.
3. Currency
Prices are displayed in the currency indicated on the website. If you are purchasing from another country, your bank may apply currency conversion fees.
4. Order Confirmation
Once your payment has been successfully processed, you will receive an order confirmation email containing your purchase details.
5. Failed or Declined Payments
If your payment is declined, please verify your billing information or contact your bank. Orders will only be processed after successful payment confirmation.
6. Fraud Prevention
BILLIONS BIRDS reserves the right to cancel or refuse any order if fraud or unauthorised activity is suspected.
Delivery Policy – BILLIONS BIRDS
At BILLIONS BIRDS, we are dedicated to delivering your orders safely and efficiently.
1. Order Processing
All orders are processed within 1–3 business days after payment confirmation. Orders are not processed or shipped on weekends or public holidays.
2. Shipping Times
Estimated delivery times vary depending on your location:
Domestic Shipping: 3–7 business days
International Shipping: 7–15 business days
Please note that delivery times are estimates and may vary due to customs procedures, carrier delays, weather conditions, or other unforeseen circumstances.
3. Shipping Costs
Shipping fees are calculated at checkout based on your location and selected shipping method. Any customs duties, taxes, or import fees are the customer's responsibility.
4. Tracking Information
Once your order has been shipped, you will receive a confirmation email with tracking details (if available) so you can monitor your package.
5. Delivery Issues
If your order is delayed, lost, or arrives damaged, please contact us within 7 days of the expected delivery date. We will work with the shipping carrier to resolve the issue as quickly as possible.
6. Incorrect Shipping Information
Customers are responsible for providing accurate shipping details at checkout. BILLIONS BIRDS is not responsible for orders shipped to incorrect addresses provided by the customer.
Refund Policy – BILLIONS BIRDS
At BILLIONS BIRDS, customer satisfaction is our top priority. If you are not completely satisfied with your purchase, we’re here to help.
1. Return Eligibility
You may request a return within 14 days of receiving your order. To qualify for a return:
The item must be unused, unworn, and in the same condition as received.
The item must be in its original packaging.
Proof of purchase (order confirmation or receipt) is required.
Certain items may not be eligible for return, including clearance items, gift cards, or personalised/custom products.
2. Non-Refundable Items
The following items are non-refundable:
Final sale or discounted items
Gift cards
Items damaged due to misuse, negligence, or improper care
3. Return Process
To initiate a return, please contact our customer support team with your order number and reason for return. If your return is approved, you will receive instructions for returning the item.
Unless the item is defective or incorrect, customers are responsible for return shipping costs.
4. Refund Processing
Once we receive and inspect your returned item:
We will notify you of the approval or rejection of your refund.
If approved, the refund will be issued to your original payment method within 5–10 business days.
Please note that banks or payment providers may require additional time to process refunds.
5. Damaged or Incorrect Items
If you receive a damaged, defective, or incorrect item, please contact us within 7 days of delivery and provide clear photos of the product and packaging. We will arrange a replacement or full refund at no additional cost.
6. Late or Missing Refunds
If you have not received your refund:
Check your bank account again.
Contact your credit card company or payment provider.
If the issue persists, don't hesitate to contact our support team for assistance.
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