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SENY Single Cylinder Deadbolt – Eternal Curve Design for Interior Doors

$45.99
The single-cylinder Suqare Deadbolt features quality components for smooth, durable performance.
  • Designed for daily use, easy DIY install
  • Fits most standard U.S. doors
  • Adjustable backset: 2-3/8" or 2-3/4"
  • Bolt Throw: 1" hardened steel
Finish:Matte Black

🚚 Free Shipping on $99+ (Standard $4.99 under $99)
⚡ Expedited Shipping Available
🔁 30-Day Returns
🛡 2-Year Warranty
💳 Visa · Mastercard · Amex · Apple Pay · Google Pay · Shop Pay · Paypal
💰 Taxes included — no hidden fees.

No APO/FPO/PO Boxes. Expedited shipping is not available for remote areas.

FAQ

  1. Can Seny hardware be customized for DIY projects?
    We offer personalized engraving services for DIY enthusiasts, making every door handle truly one of a kind and connecting the warmth of home with a personal touch.
  2. What finishes are available for door hardware?                                                        Seny Hardware offers a wide range of finishes, including Matte Black, Brushed Copper, Faux Gold, Brushed Red Bronze, Highlighted Red Bronze, Brushed Nickel, Polished Chrome, Antique Brass, Aged Brass, and Champagne Bronze — crafted to elevate any interior.
  3. Is Seny Hardware suitable for the exterior of my house?                                        Yes, our door handles and pulls are protected with a powder-coated anti-corrosion finish and have undergone rigorous quality testing for residential use. In addition, all of our hardware is thoroughly tested for quality before shipping.               
  4. How quickly can I get my order?                                                                               
    Most orders ship within 1–2 business days, and transit time varies by location—typically 2–7 days (Standard) or 1–2 days (Expedited). You’ll receive a tracking number once your package ships!
  5. Do your mortise locksets include keys?      
    Yes, the package contains one deadbolt, strike plate, latch, and two skeleton keys.
  6. What is the backset of your mortise lock?                                                                2.36"– We do not offer any other size.
  7. Will your interior mortise lock chassis fit all older doors with mortise locks?      Compatible with most interior doors and can adapt 2.36"backset.
  8. Are crystal door knobs hard to use in winter because they feel cold?                   While crystal naturally feels cooler to the touch during winter, they will warm up quickly with use.Many customers choose them because they not only function perfectly as hardware but also add a unique decorative accent that elevates the entire space.
  9. What do I do if someone locks themselves in a room?                                            There is a small hole in the Rosette or Plate on the exterior side of the door that can be used to unlock a “locked” privacy door. Insert a straightened paper clip or something of similar size into the privacy hole and gently push to unlock the privacy.

  10. Do the screw holes match?                                                                                         Generally, our screw holes and locks are designed to be compatible. If you encounter any mismatch issues, please take a photo and contact our after-sales customer service for help.                                                                                         

Select your function

Trusted by homeowners nationwide.

Over 10,000 Sets Sold in the U.S.

Reliable Interior Security with Refined Curved Design

The SENY Single Cylinder Deadbolt – Eternal Curve Series is designed for interior door applications where dependable security and refined aesthetics are required. Its softly curved profile delivers a balanced, modern look while maintaining smooth, durable performance.

Single-Sided / Single Cylinder Function

Designed as a single cylinder deadbolt, this lock features a secure locking mechanism with interior thumb turn operation—ideal for interior doors that require controlled access without exterior key entry.

Precision-Engineered Performance

Built with high-quality internal components, the deadbolt ensures smooth engagement and reliable locking performance for everyday residential use.

Solid Construction for Long-Lasting Durability

Crafted from solid materials, this deadbolt offers enhanced strength, resistance to wear, and long-term durability while maintaining a clean, refined appearance.

Complete Deadbolt Set for One Door

Includes a complete deadbolt set for one door, with pre-assembled deadbolt components to simplify installation and ensure accurate alignment.

Multiple Finish Options

Available in a variety of finishes to coordinate seamlessly with interior door hardware and overall décor styles.

Standard-Compatible Design

  • Adjustable backset: 2-3/8" or 2-3/4"

  • Fits standard U.S. door thicknesses from 1.38"–1.75"
    Designed for easy replacement or new installations.

Ideal for Interior Doors

Perfect for:

  • Interior doors

  • Bedrooms and private rooms

  • Interior security applications

Built for Everyday Use

Engineered for smooth daily operation and backed by a 2-year warranty, offering long-term confidence and reliability.

Important Notes

California Proposition 65 Warning: Cancer and Reproductive Harm – www.p65warnings.ca.gov
Due to production batch variations, slight color differences may occur.
DEADBOLT HEIGHT:2.86''
DEADBOLT WIDTH:2.19''
BACKSET:2-3/8'' or 2-3/4''
Deadbolt