---
product_id: 628613035
title: "Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack)"
brand: "captain o-ring"
price: "€ 70.54"
currency: EUR
in_stock: true
url: https://www.desertcart.nl/products/628613035-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b
store_origin: NL
region: Netherlands
---

# 2-pack for backup & replacement Exact OEM spec fit Proudly USA assembled Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack)

**Brand:** captain o-ring
**Price:** € 70.54
**Availability:** ✅ In Stock

## Summary

> 🔧 Seal the deal with confidence—never let a leak cramp your style!

## Quick Answers

- **What is this?** Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack) by captain o-ring
- **How much does it cost?** € 70.54 with free shipping
- **Is it available?** Yes, in stock and ready to ship
- **Where can I buy it?** [www.desertcart.nl](https://www.desertcart.nl/products/628613035-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b)

## Best For

- captain o-ring enthusiasts

## Why This Product

- Trusted captain o-ring brand quality
- Free international shipping included
- Worldwide delivery with tracking
- 15-day hassle-free returns

## Key Features

- • **Dual-Pack Convenience:** Includes two o-rings so you’re always prepared—replace now and keep a spare ready.
- • **Proudly Made in the USA:** Quality you can trust, assembled domestically with warranty support from Captain O-Ring LLC.
- • **Durable Synthetic Rubber:** Crafted from high-grade synthetic rubber ensuring long-lasting resilience and performance.
- • **Leak Prevention Guaranteed:** Restore your canister filter’s integrity and avoid costly water damage with a reliable seal.
- • **Precision OEM Compatibility:** Perfectly matches SunSun HW304A/B and related models for leak-proof sealing.

## Overview

Captain O-Ring’s 2-pack replacement seals are precision-engineered synthetic rubber o-rings designed to fit SunSun HW304A, HW304B, and compatible canister filters. Each ring measures approximately 9.7” ID x 10.14” OD x 0.21” thick, ensuring an exact OEM match for leak-proof performance. Proudly assembled in the USA, these durable seals come with a warranty and provide a hassle-free solution to maintain your aquarium’s filtration system with a spare always on hand.

## Description

Fix your leaking canister filter and have a spare on hand to prevent costly leaks with Captain O-Ring’s 2-pack replacement o-rings for SunSun canister filters.  This o-ring is compatible with the following canister filter models:  304A (HW304A, HW-304A), 304B (HW304B, HW-304B), 404A (HW404A, HW-404A), 404B (HW404B, HW-404B), 602 (HW602, HW-602), 602B (HW602B, HW-602B), 603 (HW603, HW-603), 603B (HW603B, HW-603B), 3000 (HW3000, HW-3000) canister filters.  Confirm your model matches one of the models above before purchasing to ensure you order the correct size that fits your filter.  These o-rings are an exact match in size, tolerance, and material to the ones that came with your canister filter when it was new. Molded from OEM spec synthetic rubber for long lasting performance and durability.  Manufactured and warrantied by Captain O-Ring LLC. Proudly assembled in the USA!

## Features

- Replacement Lid/Cover/Head Seal O-Ring for SunSun HW304A (HW-304A) and HW304B (HW-304B) canister filters, as well as the full list of compatible filters below.
- Compatible with SunSun (Sun Microsystems) 304A (HW304A), 304B (HW304B), 404A (HW404A), 404B (HW404B), 602 (HW602), 602B (HW602B), 603 (HW603), 603B (HW603B), 3000 (HW3000) canister filters.
- Approximate O-Ring Dimensions: 9.70” Inside Diameter (just under 9-3/4”), 10.14” (just over 10-1/8”), 0.21” Thick (between 3/16” and 1/4”).
- Package includes two (2) o-rings (also called gaskets, seal rings, or rubber rings). Replace your old, worn, leaking o-ring and have a spare on hand for the future with this handy 2-pack.
- Manufactured and warrantied by Captain O-Ring LLC. Proudly assembled in the USA!

## Technical Specifications

| Specification | Value |
|---------------|-------|
| Material | Rubber |
| Brand | Captain O-Ring |
| Colour | Black (Rubber) |
| UPC | 810061941538 |
| Manufacturer | Captain O-Ring LLC |
| Net Quantity | 2.0 Count |
| Country of Origin | USA |
| Model number | SS-HW304A-OR-2pk |
| Number of Memory Sticks | 2 |
| Item Weight | 50 g |
| Package Dimensions | 13.89 x 13.41 x 2.39 cm; 50 g |
| Item model number | SS-HW304A-OR-2pk |
| Are batteries included? | No |

## Product Details

- **Material:** Rubber
- **Brand:** Captain O-Ring
- **Colour:** Black (Rubber)
- **UPC:** 810061941538
- **Manufacturer:** Captain O-Ring LLC

## Images

![Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack) - Image 1](https://m.media-amazon.com/images/I/517fxzoXb4L.jpg)
![Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack) - Image 2](https://m.media-amazon.com/images/I/61oNiUKyOfL.jpg)
![Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack) - Image 3](https://m.media-amazon.com/images/I/71tnGR-ObUL.jpg)
![Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack) - Image 4](https://m.media-amazon.com/images/I/715fa7-SyzL.jpg)
![Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack) - Image 5](https://m.media-amazon.com/images/I/61xtrDC97qL.jpg)

## Frequently Bought Together

- Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack)
- Marine Color 9w Lamp Bulb, Spare Bulb for Sunsun Hw-303b 304b 404b Jup-01 Filter Cf400, Cf500, G23 2 Pin,
- Replacement Impeller for SUNSUN Aquarium Canister Filter (HW304A/HW304B)

---

## Why Shop on Desertcart?

- 🛒 **Trusted by 1.3+ Million Shoppers** — Serving international shoppers since 2016
- 🌍 **Shop Globally** — Access 737+ million products across 21 categories
- 💰 **No Hidden Fees** — All customs, duties, and taxes included in the price
- 🔄 **15-Day Free Returns** — Hassle-free returns (30 days for PRO members)
- 🔒 **Secure Payments** — Trusted payment options with buyer protection
- ⭐ **TrustPilot Rated 4.5/5** — Based on 8,000+ happy customer reviews

**Shop now:** [https://www.desertcart.nl/products/628613035-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b](https://www.desertcart.nl/products/628613035-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b)

---

*Product available on Desertcart Netherlands*
*Store origin: NL*
*Last updated: 2026-01-27*