---
product_id: 298944462
title: "Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish"
brand: "prime-line"
price: "¥7435"
currency: JPY
in_stock: true
reviews_count: 5
category: "Prime Line"
url: https://www.desertcart.jp/products/298944462-defender-security-u-10304-chain-door-guard-door-chain-lock
store_origin: JP
region: Japan
---

# 6-inch, 8-link welded steel chain Quick & easy installation with included fasteners Solid extruded brass with satin nickel finish Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish

**Brand:** prime-line
**Price:** ¥7435
**Availability:** ✅ In Stock

## Summary

> 🛡️ Lock in safety, unlock peace of mind.

## Quick Answers

- **What is this?** Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish by prime-line
- **How much does it cost?** ¥7435 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.jp](https://www.desertcart.jp/products/298944462-defender-security-u-10304-chain-door-guard-door-chain-lock)

## Best For

- prime-line enthusiasts

## Why This Product

- Trusted prime-line brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Hassle-Free Setup:** All necessary fasteners included for a swift, tool-friendly installation—security made simple.
- • **Child-Safe Placement:** Install out of reach to prevent kids from opening the door alone—peace of mind for parents.
- • **Durable Premium Build:** Crafted from solid brass and welded steel chain for long-lasting, tamper-resistant protection.
- • **Universal Fit & Style:** Compact 3-5/16” size fits most door types with a sleek satin nickel finish that complements modern interiors.
- • **Secure Ventilation Control:** Allows safe door opening for viewing & airflow without compromising security.

## Overview

The Defender Security U 10304 Chain Door Guard is a robust door security device featuring a 6-inch, 8-link welded steel chain and solid extruded brass construction with a satin nickel finish. Designed for easy installation with included fasteners, it allows safe door ventilation and viewing while preventing unauthorized entry. Its child-safe installation option and universal fit make it an essential upgrade for home or office security.

## Description

This U 10304 Chain Door Guard Lock is a security locking device for doors, allowing a door to be slightly opened to allow safe viewing and ventilation. This door lock can also be installed out of reach of children so they cannot open the door by themselves, providing additional child-safe door security. Installation is quick and easy with fasteners included, providing added security for your home or office doors. This door guard is constructed of extruded brass with a classic bronze finish and a 6 inch, 8-link welded steel chain. The 3-5/16 inch chain guard can be used on a variety of door types and can be placed over or beside door casing. It features a 6 inch long, 8-link welded steel chain and all installation fasteners necessary for complete install.

Review: Buena calidad y resistencia del material de la cadena.
Review: Os parafusos são maiores do que os buracos , tive que comprar parafusos novos

## Features

- SECURITY LOCKING DEVICE –This U 10304 Chain Door Guard is a security locking device for doors, allowing a door to be slightly opened to allow safe viewing and ventilation.
- CHILD-SAFE SECURITY DEVICE – This door chain lock can also be installed out of reach of children so they cannot open the door by themselves, providing additional child-safe door security.
- EASY INSTALLATION - Installation is quick and easy – additional security for your home or office doors are within reach! Installation fasteners are included.
- DURABLE CONSTRUCTION – This chain door guard is constructed of extruded brass with a satin nickel plated finish and a 6”, 8-link welded steel chain. It’s strong and durable and sure to last.
- PRODUCT INFO – The 3-5/16” U 10304 Chain Door Guard can be used on a variety of door types and can be placed over or beside door casing. It features a 6-inch long, 8-link welded steel chain and all installation fasteners necessary for complete install.

## Technical Specifications

| Specification | Value |
|---------------|-------|
| ASIN | B003VWPKQ8 |
| Best Sellers Rank | #95,387 in Baby Products ( See Top 100 in Baby Products ) #889 in Door & Window Guards |
| Brand | Prime-Line |
| Colour | satin nickel |
| Finish Type | Satin Nickel |
| Generic Name | Chain lock |
| Global Trade Identification Number | 00049793103048 |
| Included Components | chain lock, keeper and fasteners |
| Item Dimensions LxWxH | 8.4 x 1.6 x 5.1 Centimeters |
| Item Weight | 50 g |
| Item model number | U 10304 |
| Manufacturer | Prime-Line Products (Home Improvement) |
| Material | Alloy Steel |
| Net Quantity | 1.0 Count |
| Number of Pieces | 1 |
| Product Dimensions | 8.41 x 1.59 x 5.08 cm; 50 g |
| Style | chain |
| UPC | 049793103048 |

## Product Details

- **Brand:** Prime-Line
- **Colour:** satin nickel
- **Finish Type:** Satin Nickel
- **Global Trade Identification Number:** 00049793103048
- **Manufacturer:** Prime-Line Products (Home Improvement)
- **Material:** Alloy Steel
- **Number of Pieces:** 1
- **Style:** chain
- **UPC:** 049793103048

## Images

![Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish - Image 1](https://m.media-amazon.com/images/I/411NMJ19yRS.jpg)
![Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish - Image 2](https://m.media-amazon.com/images/I/41EztYv2WGL.jpg)
![Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish - Image 3](https://m.media-amazon.com/images/I/41eV3UbfpsL.jpg)
![Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish - Image 4](https://m.media-amazon.com/images/I/61S+fkd1IiS.jpg)
![Defender Security U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16”, Solid Brass Construction with a Satin Nickel Finish - Image 5](https://m.media-amazon.com/images/I/61dVarMBStL.jpg)

## Customer Reviews

### ⭐⭐⭐⭐⭐ Review
*by C***N on 16 April 2025*

Buena calidad y resistencia del material de la cadena.

### ⭐⭐⭐ Review
*by D***S on 20 March 2024*

Os parafusos são maiores do que os buracos , tive que comprar parafusos novos

### ⭐⭐⭐⭐⭐ Review
*by J***S on 17 January 2025*

Easy as heck to install, nice and shiny

## Frequently Bought Together

- Prime-Line U 10304 Chain Door Guard – Door Chain Lock for Door and Home Security, 3-5/16 In., Solid Brass Construction with a Satin Nickel Finish (Single Pack)
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*Product available on Desertcart Japan*
*Store origin: JP*
*Last updated: 2026-02-08*