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Waterproof Sealant Mastic
Waterproof Sealant Mastic
Waterproof Sealant Mastic
Waterproof Sealant Mastic
Waterproof Sealant Mastic
Waterproof Sealant Mastic

Waterproof Sealant Mastic

4.8/5 (1877 Reviews)
$19.95
$40.00 
50% off

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Trusted by 12,000+ Customers

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Only 11 Left In Stock!
Ships By: Mar 26
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(5/5)

"Been shopping here since 2023 and it's become my go-to store. Never had a bad experience, always consistent quality!"

-Lisa L.

Verified Purchase • Jan 8, 2026

Shipping & Delivery

We offer Secure Shipping on all orders. Your order will be processed within 1-2 business days and delivered in 3-7 business days depending on your location. Once shipped, you'll receive a tracking number via email so you can monitor your package every step of the way. For any questions, contact us at info@mao-wow.com.

Returns & Refunds

Your satisfaction is our priority. If you're not completely happy with your purchase, we offer a 30-day money-back guarantee. Simply contact us at info@mao-wow.com and we'll guide you through our easy return process. Once received, we'll issue a full refund within 5-7 business days. No questions asked—shop with complete confidence.

12,000+ 
Happy Customers

Money-Back 
Guarantee

Fast Delivery &
Easy Returns

(5/5)

"Been shopping here since 2023 and it's become my go-to store. Never had a bad experience, always consistent quality!"

-Lisa L.

Verified Purchase • Jan 8, 2026

Shipping & Delivery

We offer Secure Shipping on all orders. Your order will be processed within 1-2 business days and delivered in 3-7 business days depending on your location. Once shipped, you'll receive a tracking number via email so you can monitor your package every step of the way. For any questions, contact us at info@mao-wow.com.

Returns & Refunds

Your satisfaction is our priority. If you're not completely happy with your purchase, we offer a 30-day money-back guarantee. Simply contact us at info@mao-wow.com and we'll guide you through our easy return process. Once received, we'll issue a full refund within 5-7 business days. No questions asked—shop with complete confidence.

12,000+ 
Happy Customers

Money-Back 
Guarantee

Fast Delivery &
Easy Returns

12,000+ 
Happy Customers

Money-Back 
Guarantee

Fast Delivery &
Easy Returns

Shipping & Delivery

We offer Secure Shipping on all orders. Your order will be processed within 1-2 business days and delivered in 3-7 business days depending on your location. Once shipped, you'll receive a tracking number via email so you can monitor your package every step of the way. For any questions, contact us at info@mao-wow.com.

Returns & Refunds

Your satisfaction is our priority. If you're not completely happy with your purchase, we offer a 60-day money-back guarantee. Simply contact us at info@mao-wow.com and we'll guide you through our easy return process. Once received, we'll issue a full refund within 5-7 business days. No questions asked—shop with complete confidence.

SPECIFICATIONS:

Material: Mastic
Weight: 21.5g
Package size: 133*61mm

Easy to use, save money for maintenance workers!

EASY TO USE

  • 🌍 Reshape the clay depending on the size of the hole/gap.
  • 🌍 Can be perfectly blended with the surface.
  • 🌍 Air-dry in only about 10 minutes. Flame retardant and waterproof.

HIGHLY FLEXIBLE & DURABLE: Final membrane has over 1000% elongation preventing adhesion failure, and is UV stable to prevent sun degradation.

PROTECTIVE FINISH FOR: Flat roofs, metal roofs, sloped roofs, planter boxes, foundations, sheds, basements, metal, wood, concrete, and more.

🌍 Environmental protection materials, care for your health 🌍

FAQ

Q: Can you paint over this product?

A: Absolutely! I have used this product all throughout my poured concrete basement and then painted over it. Looks great!

Q: Can this be used to seal around a heating pipe, or can you recommend something else?

A: It expands to fill holes, cracks, gaps, and voids around windows, doors, pipes, outlets, vents, so it should work fine for this purpose.

🎁 It's a perfect gift for your family & friends!

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    FAQs

    Got questions? We’ve got answer...

    What payment methods do you accept?

    We accept all major payment methods including Visa, Mastercard, American Express, Shop Pay, Apple Pay, and Google Pay. All transactions are processed through secure, encrypted payment gateways to protect your information. You'll never be charged until your order is confirmed, and you'll receive an email receipt immediately after purchase.

    What if the product doesn't work or I don't like it?

    We've got you covered with our 60-day money-back guarantee. If you're not completely satisfied for any reason, simply contact us and we'll process a full refund—no questions asked. We want you to shop with complete confidence, which is why we make returns hassle-free.

    How long will shipping take?

    Orders are processed within 1-2 business days and typically arrive in 3-7 business days depending on your location. All orders include free worldwide shipping and a tracking number so you can monitor your delivery. Most customers receive their orders within 7-10 days.

    Can I track my order?

    Yes! Once your order ships, you'll receive a tracking number via email within 24 hours. You can also track your order anytime by visiting our "Track Your Order" page at the top of the website. If you have any issues with tracking, our support team is here to help.

    What if my item arrives damaged or defective?

    We carefully package every order, but if something arrives damaged or defective, we'll make it right immediately. Just email us a photo at info@mao-wow.com within 48 hours of delivery, and we'll send a free replacement or issue a full refund—whichever you prefer. Your satisfaction is our guarantee.

    MAO-WOW

    Hear from Our Customers

    2000+ Customers Who Love Us

    Emily

    Customer 

    Verified Buyer

    No complaints

    “I was skeptical about ordering online but these exceeded my expectations. The quality is great and shipping was faster than I thought. Definitely ordering again!”

    Sarah

    Customer 

    Verified Buyer

    Happy with my order

    “Took about 9 days to arrive which was within the timeframe they mentioned. Everything came exactly as shown in the photos and the quality seems solid. Tracking worked fine and kept me updated throughout. Would order again.”

    Ken K

    Customer 

    Verified Buyer

    Good experience overall

    “Finally found an online store I can trust! Their products are exactly as advertised, shipping is quick, and they actually respond when you have questions. Highly recommend giving them a try!”

    Michael

    Customer 

    Verified Buyer

    Better than I expected!

    “Was worried about quality but this is actually really good! Arrived quickly, well packaged, and works great. No complaints at all. Thank you!”

    Jessica

    Customer 

    Verified Buyer

    Highly recommend!

    "I've shopped here multiple times now and they never disappoint. The customer service is responsive, shipping is reliable, and everything I've received has been high quality. Rare to find a store this consistent!”

    Olivia

    Customer 

    Verified Buyer

    No complaints!

    “Ordered for the first time and was really impressed. My package arrived in 8 days with full tracking, everything was well-packaged, and the quality matched the descriptions. Will definitely shop here again!”

    Hear from Our Customers

    12,000+ Customers Who Love Us

    Michael L.

    Customer 

    Verified Buyer

    Better than I expected!

    “Was worried about quality but this is actually really good! Arrived quickly, well packaged, and works great. No complaints at all. Thank you!”

    Jessica

    Customer 

    Verified Buyer

    Highly recommend!

    "I've shopped here multiple times now and they never disappoint. The customer service is responsive, shipping is reliable, and everything I've received has been high quality. Rare to find a store this consistent!”

    Olivia

    Customer 

    Verified Buyer

    So Fast!

    “Ordered for the first time and was really impressed. My package arrived in 8 days with full tracking, everything was well-packaged, and the quality matched the descriptions. Will definitely shop here again!”

    Emily k.

    Customer 

    Verified Buyer

    No complaints

    “I was skeptical about ordering online but these exceeded my expectations. The quality is great and shipping was faster than I thought. Definitely ordering again!”

    Sarah

    Customer 

    Verified Buyer

    Happy with my order

    “Took about 9 days to arrive which was within the timeframe they mentioned. Everything came exactly as shown in the photos and the quality seems solid. Tracking worked fine and kept me updated throughout. Would order again.”

    Ken K

    Customer 

    Verified Buyer

    Good experience overall

    “Finally found an online store I can trust! Their products are exactly as advertised, shipping is quick, and they actually respond when you have questions. Highly recommend giving them a try!”

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