--- product_id: 51559763 title: "C21CP-C Caulk Saver Bulk Contractor Pack, 3/8-inch Diameter x 350-feet Long, Grey" brand: "frost king" price: "428 zł" currency: PLN in_stock: true reviews_count: 13 category: "Frost King" url: https://www.desertcart.pl/products/51559763-c21cp-c-caulk-saver-bulk-contractor-pack-3-8-inch store_origin: PL region: Poland --- # Moisture-resistant foam 350 feet continuous length C21CP-C Caulk Saver Bulk Contractor Pack, 3/8-inch Diameter x 350-feet Long, Grey **Brand:** frost king **Price:** 428 zł **Availability:** ✅ In Stock ## Summary > 💼 Seal smarter, save bigger — the pro’s secret weapon for flawless finishes! ## Quick Answers - **What is this?** C21CP-C Caulk Saver Bulk Contractor Pack, 3/8-inch Diameter x 350-feet Long, Grey by frost king - **How much does it cost?** 428 zł with free shipping - **Is it available?** Yes, in stock and ready to ship - **Where can I buy it?** [www.desertcart.pl](https://www.desertcart.pl/products/51559763-c21cp-c-caulk-saver-bulk-contractor-pack-3-8-inch) ## Best For - frost king enthusiasts ## Why This Product - Trusted frost king brand quality - Free international shipping included - Worldwide delivery with tracking - 15-day hassle-free returns ## Key Features - • **Built to Last:** Crafted from resilient polyurethane foam that resists moisture and maintains shape under pressure. - • **Perfect Fit Every Time:** 3/8-inch diameter foam designed to snugly fill gaps, ensuring a flawless seal and professional finish. - • **Effortless Installation:** Flexible yet sturdy foam that’s easy to handle, install, and won’t crumble or tear mid-project. - • **Trusted by Pros, Loved by DIYers:** Join thousands of satisfied users who’ve upgraded their sealing game with Frost King’s reliable caulk saver. - • **Maximize Efficiency, Minimize Waste:** Stretch your caulk budget further with 350 feet of durable foam that reduces excess usage. ## Overview The Frost King C21CP-C Caulk Saver is a 3/8-inch diameter, 350-foot long grey polyurethane foam backer rod designed to reduce caulk usage and improve sealing efficiency. Moisture-resistant and durable, it’s easy to install and ideal for filling gaps in walls, making it a cost-effective solution favored by contractors and DIY enthusiasts alike. ## Description Frost King C21CP-C Caulk Saver Bulk Contractor Pack, 3/8-inch Diameter x 350-feet Long, Grey Review: Reliable Foam Backer That Saves Time and Money - I bought this foam backer to use with caulking around my kitchen wood floor, and it worked better than expected. The material is sturdy yet flexible, making it simple to install without tearing or crumbling. It held its shape, created a clean base, and significantly reduced the amount of caulk I needed to use. I also appreciate that it’s moisture-resistant, which gives me peace of mind. For anyone tackling sealing jobs, this is a cost-effective and dependable solution that makes the work quicker and easier. Review: Works well. - Should have bought this from the start. I kept buying small amounts from Floor and Decor. Works well, very easy to use and flexible. The size is also perfect for small gaps. Definitely recommend it. ## Features - Foam - Saves on expensive caulk - Works with virtually all caulk - Moisture repellant - Made of durable, resilient poly foam - Easy to use and install ## Technical Specifications | Specification | Value | |---------------|-------| | ASIN | B016PA9VBW | | Batteries Included? | No | | Batteries Required? | No | | Best Sellers Rank | #50,526 in Tools & Home Improvement ( See Top 100 in Tools & Home Improvement ) #312 in Weather Stripping | | Brand | Frost King | | Color | Gray | | Customer Reviews | 4.6 4.6 out of 5 stars (903) | | Date First Available | October 15, 2015 | | Global Trade Identification Number | 00077578060262 | | Included Components | Poly Foam Caulk Saver | | Item Form | Foam | | Item Package Quantity | 1 | | Item Weight | 15.4 ounces | | Item model number | C21CP-C | | Manufacturer | Frost King | | Material | Polyurethane | | Maximum Gap Fill | 3.8 Centimeters | | Number of Items | 1 | | Part Number | C21CP-C | | Product Dimensions | 12 x 9.88 x 10.25 inches | | Size | 3/8" x diam. x 350 ft | | Style | 3/8"D X 350'L | | Surface Recommendation | Walls | | UPC | 077578060262 | | Unit Count | 350.0 Feet | | Water Resistance Level | Water Resistant | ## Product Details - **Brand:** Frost King - **Color:** Gray - **Item Form:** Foam - **Item Weight:** 15.36 ounces - **Maximum Gap Fill:** 3.8 Centimeters ## Images ![C21CP-C Caulk Saver Bulk Contractor Pack, 3/8-inch Diameter x 350-feet Long, Grey - Image 1](https://m.media-amazon.com/images/I/91TZMmHjiRL.jpg) ## Available Options This product comes in different **Style** options. ## Questions & Answers **Q: Is this waterproof? Would like to use prior to caulking outside of my cabin** A: It is waterproof. I would be sure to seal it with some sort of caulk afterwards though **Q: Is this polyurethane foam?** A: I think so **Q: Is this closed cell backer Rod?** A: I don't know, but it was what i needed to fill cracks. **Q: What type tool is best for pushing this into the crevice?** A: I am sure you can find a good tool under caulk finishing or application. I just used my finger and the butt of a small round screwdriver. My project was not typical. ## Customer Reviews ### ⭐⭐⭐⭐⭐ Reliable Foam Backer That Saves Time and Money *by H***A on September 16, 2025* I bought this foam backer to use with caulking around my kitchen wood floor, and it worked better than expected. The material is sturdy yet flexible, making it simple to install without tearing or crumbling. It held its shape, created a clean base, and significantly reduced the amount of caulk I needed to use. I also appreciate that it’s moisture-resistant, which gives me peace of mind. For anyone tackling sealing jobs, this is a cost-effective and dependable solution that makes the work quicker and easier. ### ⭐⭐⭐⭐⭐ Works well. *by T***S on December 22, 2025* Should have bought this from the start. I kept buying small amounts from Floor and Decor. Works well, very easy to use and flexible. The size is also perfect for small gaps. Definitely recommend it. ### ⭐⭐⭐⭐ Great Price! *by T***H on May 25, 2020* Great Value! ## Frequently Bought Together - Frost King C21CP-C Caulk Saver Bulk Contractor Pack, 3/8-inch Diameter x 350-feet Long, Grey - Mutual Industries Standard Backer Rod, 4000 Linear Feet, 1/4" - 1/2" Diameter x 200' Length Backer Rod Caulk Saver Foam Backer Rod for Gaps and Joints Backing Concrete Filler --- ## 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.pl/products/51559763-c21cp-c-caulk-saver-bulk-contractor-pack-3-8-inch](https://www.desertcart.pl/products/51559763-c21cp-c-caulk-saver-bulk-contractor-pack-3-8-inch) --- *Product available on Desertcart Poland* *Store origin: PL* *Last updated: 2026-05-26*