--- product_id: 592084472 title: "Captain O-Ring – Replacement Seal Oring for SunSun HW304A, HW304B Canister Filter (2 Pack)" brand: "captain o-ring" price: "₨343" currency: SCR in_stock: true category: "Captain O Ring" url: https://www.desertcart.sc/products/592084472-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b store_origin: SC region: Seychelles --- # Durable synthetic rubber 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:** ₨343 **Availability:** ✅ In Stock ## Summary > 🛡️ Seal your filter’s fate with confidence—never let leaks cramp your aquatic vibe! ## 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?** ₨343 with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.sc](https://www.desertcart.sc/products/592084472-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 - • **Optimal Dimensions:** 9.7” inside diameter with 0.21” thickness ensures a snug, reliable seal every time. - • **Dual-Pack Convenience:** Two premium o-rings included—fix now and keep a spare for future peace of mind. - • **Durable Synthetic Rubber:** Engineered for long-lasting leak-proof performance under pressure. - • **Trusted Quality & Warranty:** Manufactured and backed by Captain O-Ring LLC, guaranteeing premium reliability. - • **Precision OEM Compatibility:** Perfectly matches SunSun HW304A/B and related models for hassle-free replacement. ## 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. With exact OEM dimensions and durable material, these USA-assembled gaskets prevent leaks and ensure long-term filter performance, making them an essential upgrade for any serious aquarium enthusiast. ## 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) 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) 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 | |---------------|-------| | ASIN | B0CP6C1FFD | | Best Sellers Rank | #53,210 in Pet Supplies ( See Top 100 in Pet Supplies ) #646 in Aquarium Filter Accessories | | Brand Name | Captain O-Ring | | Color | Black (Rubber) | | Customer Reviews | 4.0 4.0 out of 5 stars (78) | | Item Diameter | 9.7 inches | | Manufacturer | Captain O-Ring LLC | | Material Type | Rubber | | Model | SS-HW304A-OR-2pk | | Nominal Inside Diameter | 9.7 inches | | Nominal Outside Diameter | 10.14 inches | | Number of Items | 2 | | Number of Pieces | 2 | | Part Number | SS-HW304A-OR-2pk | | Set Name | Captain O-Ring Replacement Seal O-Ring 2-Pack for SunSun HW304A/HW304B | | UPC | 810061941538 | | Unit Count | 2 Count | ## Product Details - **Brand:** Captain O-Ring - **Color:** Black (Rubber) - **Item Diameter:** 9.7 inches - **Material:** Rubber - **Nominal Inside Diameter:** 9.7 inches ## 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) ## 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.sc/products/592084472-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b](https://www.desertcart.sc/products/592084472-captain-o-ring-replacement-seal-oring-for-sunsun-hw304a-hw304b) --- *Product available on Desertcart Seychelles* *Store origin: SC* *Last updated: 2026-10-18*