--- product_id: 49495877 title: "W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape" brand: "w4" price: "Β₯6139" currency: JPY in_stock: true reviews_count: 13 url: https://www.desertcart.jp/products/49495877-w4-mastic-sealing-strip-19mm-x-5m-white-waterproof-butyl store_origin: JP region: Japan --- # 100% Waterproof Seal 19mm x 5m Precision Fit Flexible Non-Setting Mastic W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape **Brand:** w4 **Price:** Β₯6139 **Availability:** βœ… In Stock ## Summary > πŸ’§ Seal Smart, Travel Confident: The Ultimate Waterproof Shield for Your Adventure Mobile ## Quick Answers - **What is this?** W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape by w4 - **How much does it cost?** Β₯6139 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/49495877-w4-mastic-sealing-strip-19mm-x-5m-white-waterproof-butyl) ## Best For - w4 enthusiasts ## Why This Product - Trusted w4 brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - β€’ **Flexible & Durable:** Non-setting mastic stays soft, preventing cracks from movement and vibration. - β€’ **Ultimate Leak Defense:** Keep your caravan dry and worry-free with trusted waterproof protection. - β€’ **Versatile Application:** Seals windows, roof lights, vents, doors, trims, and exterior joints effortlessly. - β€’ **Precision Width & Length:** Perfectly sized 19mm x 5m strip for narrow joints and trims. - β€’ **No-Mess, No-Wait Installation:** Apply instantly with zero curing timeβ€”seal and go! ## Overview The W4 Mastic Sealing Strip is a 19mm wide, 5m long waterproof, non-setting butyl mastic tape designed for caravans and motorhomes. It provides flexible, durable sealing for windows, roof lights, vents, and trims, preventing leaks and cracks caused by movement. Easy to install with no curing time, it ensures a reliable, mess-free seal that keeps your vehicle protected on every journey. ## Description The is a specially formulated product designed for the sealing and re-bedding of various caravan and motorhome fittings. This high-quality sealing strip is perfect for use on , , , , , and most . The versatile mastic strip offers a reliable solution for sealing a range of materials and components, including , , , and more. Ideal for both repairs and installations, this sealing strip ensures a long-lasting, weather-resistant seal, keeping your caravan or motorhome fittings securely in place and protected from the elements. Whether you're maintaining your vehicle or upgrading external features, the W4 Mastic Sealing Strip is a must-have for ensuring a professional, durable finish. White 19mm White 32mm White 45mm Grey 19mm Grey 32mm Grey 45mm ## Features - WATERPROOF BUTYL SEAL – High-performance W4 white butyl mastic tape forms a waterproof seal around caravan and motorhome fittings, helping protect joints, trims and exterior fittings against water penetration. - REMAINS FLEXIBLE – Specially formulated butyl sealing strip remains flexible throughout its service life, helping accommodate normal movement around caravan and motorhome fittings without hardening or cracking. - CARAVAN & MOTORHOME USE – Designed for sealing and re-bedding rooflights, vents, awning rails, window surrounds, exterior lights, grab handles, aluminium mouldings, overlap joints and external trims. - UV RESISTANT & HIGH ADHESION – Good UV resistance provides long-lasting performance for exposed exterior applications, while excellent adhesion helps create a secure and reliable seal. - 19MM x 5M NARROW SEALING STRIP – Supplied as a 19mm wide x 5m roll, providing a practical narrow sealing width for smaller caravan and motorhome fittings, trims and joints. ## Technical Specifications | Specification | Value | |---------------|-------| | Asin | B00J0X1BUQ | | Best Sellers Rank | 8,519 in DIY & Tools (See Top 100 in DIY & Tools) 211 in Sealers | | Brand | W4 | | Colour | White | | Customer Reviews | 4.6 4.6 out of 5 stars (2,065) 4.6 out of 5 stars | | Global Trade Identification Number | 05019328001168 | | Included Components | Sealing Strip 5m | | Item Dimensions L X W | 14L x 16W centimetres | | Item Highlight | Flexible UV resistant sealant for caravan rooflights, windows, awning rails, vents, exterior trims and re-bedding fittings | | Item Thickness | 19 Millimetres | | Item Type Name | W4 W4 Narrow Mastic Sealing Strip - 5m x 19mm - White, | | Manufacturer | W4 | | Material | Butyl | | Model Number | 00116 | | Number Of Items | 1 | | Number Of Packs | 1 | | Part Number | 00116 | | Recommended Uses For Product | Sealing overlap joints, awning rails, roof-lights, vents, window surrounds, and external trims on caravans and motorhomes | | Unit Count | 5.0 meter | ## Product Details - **Brand:** W4 - **Colour:** White - **Item thickness:** 19 Millimetres - **Material:** Butyl - **Product dimensions:** 14L x 16W centimetres ## Images ![W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape - Image 1](https://m.media-amazon.com/images/I/613Js-CRpBL.jpg) ![W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape - Image 2](https://m.media-amazon.com/images/I/71VOgnVhwmL.jpg) ![W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape - Image 3](https://m.media-amazon.com/images/I/71jHaReWyLL.jpg) ![W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape - Image 4](https://m.media-amazon.com/images/I/710ia+m-kSL.jpg) ![W4 Mastic Sealing Strip 19mm x 5m White Waterproof Butyl Caravan Tape - Image 5](https://m.media-amazon.com/images/I/710ARHxKiFL.jpg) ## Available Options This product comes in different **Colour Name, Size Name** options. ## Questions & Answers **Q: Is this double-sided and sticky - so it would stick and seal polycarbonate sheeting to its wood frame?** A: Not sure about sticking to polycarbonate but as a sealing strip it worked brilliantly to my motorhome GRP body! The parts ultimately were screwed together so if this is the same assembly method you should be fine **Q: Would this be suitable to fix a cycle rack leaking braket on the back of the moho - was thinking loosening, cleaning and then resealing with this** A: I used it for reselling the Truma water heater flange to the outside of the caravan. I found the mastic tape to be too thick and difficult to work with. I think you would be better using CT1 Sealant or similar which I used to bond and seal the mounting feet of the Solar Panel, to the Caravans roof. Hope this helps. **Q: Is this tape double sided** A: Yes it is, once the protective non-stick separator tape is removed. It is simply there to stop the mastic sticking to itself and to aid installation. **Q: Will it stick to silicone sealent around a van roof vent?** A: Yes, it will stick to just about anything you apply it to. However, I have resealed a roof light/vent before and what you are planning is not your best course of action. You should remove the roof vent completely, and then use a silicone removal solution to remove the old silicone from both mating surfaces. Note, silicone should never have been used to seal it in the first place. You can buy a small bottle of silicone remover from Screwfix for around Β£5. Then buy the wide mastic sealing strip, (Not the narrow). Then refit the roof vent. When you have screwed it down, any excess mastic that squeezes out can easily be removed by wiping it off using white spirits. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Good quality and very sticky *by on Reviewed in the United Kingdom 13 August 2026* 5mx32mm arrived ahead of the estimated delivery. Very good quality sealing tape, very sticky so position carefully as you won't move it easily. I removed the old sealant around a joint on my caravan, scraping off as much old sealant as possible, then removed the residue with white spirit. I then wiped the joint with methylated spirits. When clean and dry I carefully positioned the tape pressing it down using a wallpapering roller on the backing paper to get a good bond. I then pulled the backing paper off and fitted the trim and original screws. The finished seal looks high quality; and hopefully no more damp inside the caravan. ### ⭐⭐⭐⭐⭐ Strong and Reliable *by on Reviewed in the United Kingdom 23 June 2023* I recently purchased the W4 High Performance Mastic Sealing Strip, and I must say it has proven to be an excellent product. This short review aims to highlight the strength and reliability of this sealing strip based on my experience.The W4 High Performance Mastic Sealing Strip offers exceptional strength when it comes to sealing various surfaces. Whether I'm working on my caravan, motorhome, or any other application that requires a reliable seal, this product delivers outstanding performance.One of the standout features of this sealing strip is its remarkable adhesive strength. It securely bonds to different materials, including metal, plastic, glass, and rubber, ensuring a tight and long-lasting seal. The strip creates a barrier against water, dust, and other contaminants, providing added protection and durability.The sealing strip's high-performance mastic material is resistant to harsh weather conditions, UV rays, and temperature fluctuations. This resilience allows it to maintain its strength and effectiveness over time, making it suitable for both indoor and outdoor applications. It provides peace of mind, knowing that the seal remains intact even in challenging environments.Furthermore, the W4 High Performance Mastic Sealing Strip is easy to use. It can be cut to the desired length and applied directly to the intended area. The strip conforms well to irregular surfaces, ensuring a complete and secure seal. Its flexibility allows for easy installation around corners and curves without compromising its strength.The versatility of this sealing strip is worth mentioning as well. It can be used in various applications, including sealing joints, filling gaps, and preventing leaks. Whether it's for automotive purposes, household repairs, or DIY projects, the W4 High Performance Mastic Sealing Strip proves to be a reliable and multipurpose solution.In conclusion, the W4 High Performance Mastic Sealing Strip is a must-have for anyone in need of a strong and reliable seal. Its impressive adhesive strength, durability, and versatility make it a valuable addition to any toolkit or repair supplies.If you're looking for a sealing strip that offers exceptional strength and reliability, look no further. The W4 High Performance Mastic Sealing Strip will exceed your expectations and provide a long-lasting seal in various applications. ### ⭐⭐⭐⭐ A MUST FOR CARAVANS & VANS. *by on Reviewed in the United Kingdom 4 September 2026* W4 Mastic Sealing Strip 19mm x 5mm.White Waterproof Butyl Tape.Great Quality for fitting Windows/Skylights inVans and Caravans.Used this many times and never had a Leak.Ideal for the uneven ridges in Van Roofs (do not useSilicone too thick).Use this and finish off with a bead of silicone and you will not get leaks (as long as roof is Clean&de-greased).Worth the Money for Peace of mind.I would give it 5 Stars if cheaper. ## Frequently Bought Together - W4 Mastic Sealing Strip for Caravans & Motorhomes White 19mm – Weatherproof Sealant for Overlap Joints, Awning Rails, Roof-Lights, Window Surrounds & External Trims, Durable & Easy to Apply - Sika Sikaflex-522 Caravan And Motorhome Adhesive Sealant – Weather And Mould Resistant – White – 300ml - Sikaflex-522 weather-resistant, UV-stable, adhesive sealant (new version of Sikaflex-521 UV and Sikaflex-221i) 300ml black --- ## Why Shop on Desertcart? - πŸ›’ **Trusted by 1.3+ Million Shoppers** β€” Serving international shoppers since 2016 - 🌍 **Shop Globally** β€” Access 737+ million products across 21 categories - πŸ’° **No Hidden Fees** β€” All customs, duties, and taxes included in the price - πŸ”„ **15-Day Free Returns** β€” Hassle-free returns (30 days for PRO members) - πŸ”’ **Secure Payments** β€” Trusted payment options with buyer protection - ⭐ **TrustPilot Rated 4.5/5** β€” Based on 8,000+ happy customer reviews **Shop now:** [https://www.desertcart.jp/products/49495877-w4-mastic-sealing-strip-19mm-x-5m-white-waterproof-butyl](https://www.desertcart.jp/products/49495877-w4-mastic-sealing-strip-19mm-x-5m-white-waterproof-butyl) --- *Product available on Desertcart Japan* *Store origin: JP* *Last updated: 2026-09-30*