--- product_id: 234907999 title: "Crafter Blue CB03 20mm Watch Strap Curved End Rubber Band Replacement for Seiko MM300 MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021(SLA019J1), SBDX025, SBDX023, SLA023J1(SLA021J1) etc" brand: "crafter blue" price: "FREE" currency: SGD in_stock: false reviews_count: 5 url: https://www.desertcart.sg/products/234907999-crafter-blue-cb03-20mm-watch-strap-curved-end-rubber-band store_origin: SG region: Singapore --- # Curved end design for perfect Seiko MM300 fit Includes replacement spring bars for easy install Pure vulcanized rubber for superior strength Crafter Blue CB03 20mm Watch Strap Curved End Rubber Band Replacement for Seiko MM300 MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021(SLA019J1), SBDX025, SBDX023, SLA023J1(SLA021J1) etc **Brand:** crafter blue **Price:** FREE **Availability:** ❌ Out of Stock ## Summary > ⌚ Elevate your Seiko MM300 game with the ultimate rubber strap upgrade! ## Quick Answers - **What is this?** Crafter Blue CB03 20mm Watch Strap Curved End Rubber Band Replacement for Seiko MM300 MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021(SLA019J1), SBDX025, SBDX023, SLA023J1(SLA021J1) etc by crafter blue - **How much does it cost?** FREE with free shipping - **Is it available?** Currently out of stock - **Where can I buy it?** [www.desertcart.sg](https://www.desertcart.sg/products/234907999-crafter-blue-cb03-20mm-watch-strap-curved-end-rubber-band) ## Best For - crafter blue enthusiasts ## Why This Product - Trusted crafter blue brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Comfort Meets Style:** Ergonomically designed thickness (4.5mm to 3.5mm) balances robustness with all-day comfort. - • **Unmatched Durability:** Crafted from pure vulcanized rubber, resisting oils and acids better than natural rubber for long-lasting wear. - • **Seamless Compatibility:** Precision curved ends engineered exclusively for Seiko MM300 models, ensuring a flawless, factory-like fit. - • **Effortless Installation:** Comes with replacement spring bars, so upgrading your strap is quick and hassle-free. - • **Eco-Conscious & Hypoallergenic:** RoHS-compliant material minimizes allergic reactions, perfect for sensitive skin and mindful consumers. ## Overview The Crafter Blue CB03 is a premium 20mm curved end rubber watch strap designed specifically for Seiko MM300 MarineMaster models. Made from pure vulcanized rubber, it offers superior durability and resistance to oils and acids, while meeting RoHS standards for safety. With a perfect fit, ergonomic thickness, and included spring bars, it combines comfort, style, and easy installation for the discerning watch enthusiast. ## Description CRAFTER BLUE CB03 curved end rubber band replacement for Seiko MM300. The rubber band is made of pure vulcanized rubber which has superior strength and more resistant than natural rubber to oils and acids. Material has also met the RoHS requirements and rarely causes severe allergic reaction. It also includes a pair of replacement spring bars for easy installation. Item no. : CB03 Brand Name: CRAFTER BLUE Lug width: 20mm Buckle size: 18mm Buckle Include : No Buckle type / Finish : (Compatible with 18mm Seiko MM300 buckle) Overall Length: 90mm + 55mm (Strap length:145mm / 5.71") Thickness: Approx. 4.5mm - 3.5mm Spring bar hole dia.: 2.50mm Compatible with: MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021 (SLA019J1) and SBDX023 (SLA021J1), SBDX025, SLA023J1 Material: NBR Rubber Color / Finish: Black, Brown, Orange Lug end style: Curved End Review: Major improvement to an otherwise perfect watch - Switched out the bracelet and haven’t looked back. First off, the watch is way more comfortable with the rubber strap. The straps fitment is spot on - no play at all between the straps fitment and lug. The quality is great - rubber is thick and sturdy but still comfortable for everyday use. The appearance of the watch is what I would call sportier, which I’m keen to. Used the stock mm300 ratcheting clasp with no issues. The 6’oclock side of the rubber strap is fixed you adjust my shortening the 12’oclock strap. For ref my wrist is about 7inches and it fits perfect. Bought Ken for each of my mm300s Review: Buena calidad de extensible - Es una buena calidad, tiene buen volumen de extensible, los chinos son más delgados y tienen detalles de rebaba... considero un poco elevado el costo pero si vale la pena. ## Features - CRAFTER BLUE CB03 20mm curved end watch strap replacement watch band for Seiko MM300 - 20mm rubber watch strap compatible with Seiko MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021 (SLA019J1) and SBDX023 (SLA021J1), SBDX025, SLA023J1 - Lug width: 20mm; Buckle size: 18mm; Note: Buckle is NOT included, please use your original buckle. - The NBR CRAFTER BLUE rubber strap is made of pure vulcanized rubber which has superior strength and more resistant than natural rubber to oils and acids - Overall Length: 90mm + 55mm (Strap length:145mm / 5.71"); Thickness: Approx. 4.5mm - 3.5mm; Spring bar hole dia.: 2.50mm ## Technical Specifications | Specification | Value | |---------------|-------| | Care instructions | Clean with mild soap and water, dry thoroughly after use, avoid extreme heat and chemicals. | ## Images ![Crafter Blue CB03 20mm Watch Strap Curved End Rubber Band Replacement for Seiko MM300 MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021(SLA019J1), SBDX025, SBDX023, SLA023J1(SLA021J1) etc - Image 1](https://m.media-amazon.com/images/I/51umK-3YAOL.jpg) ## Customer Reviews ### ⭐⭐⭐⭐⭐ Major improvement to an otherwise perfect watch *by J***C on 24 January 2026* Switched out the bracelet and haven’t looked back. First off, the watch is way more comfortable with the rubber strap. The straps fitment is spot on - no play at all between the straps fitment and lug. The quality is great - rubber is thick and sturdy but still comfortable for everyday use. The appearance of the watch is what I would call sportier, which I’m keen to. Used the stock mm300 ratcheting clasp with no issues. The 6’oclock side of the rubber strap is fixed you adjust my shortening the 12’oclock strap. For ref my wrist is about 7inches and it fits perfect. Bought Ken for each of my mm300s ### ⭐⭐⭐⭐⭐ Buena calidad de extensible *by A***E on 20 February 2025* Es una buena calidad, tiene buen volumen de extensible, los chinos son más delgados y tienen detalles de rebaba... considero un poco elevado el costo pero si vale la pena. ### ⭐ Ripped at the holes *by C***B on 28 January 2026* unfortunately I cut it to size before realizing that 2 of the holes are ripped, so cannot return. Otherwise it seem to be a nice band, just I can’t trust it with the material so brittle at the holes ## Frequently Bought Together - Crafter Blue CB03 Curved End Watch Band Rubber Strap Replacement for Seiko MM300 MarineMaster SBDX001, SBDX003, SBDX005, SBDX017, SBDX021(SLA019J1), SBDX025, SBDX023, SLA023J1(SLA021J1) etc - MiLTAT 18mm Wetsuit Ratchet Buckle Diver Extension Clasp, 316L Stainless Steel Brushed --- ## 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.sg/products/234907999-crafter-blue-cb03-20mm-watch-strap-curved-end-rubber-band](https://www.desertcart.sg/products/234907999-crafter-blue-cb03-20mm-watch-strap-curved-end-rubber-band) --- *Product available on Desertcart Singapore* *Store origin: SG* *Last updated: 2026-10-14*