Zinc-coated screws, often known as galvanized screws, are not entirely rust-proof but are significantly more resistant to corrosion than bare steel screws. The zinc coating acts as a sacrificial layer. When exposed to moisture or corrosive elements, it corrodes preferentially, protecting the underlying steel from rust. However, the protection is finite; once the zinc layer wears away or is damaged, the steel can start to rust. The longevity of the protection depends on the environment; in highly corrosive environments like coastal areas, the zinc can corrode more quickly. For applications where rust prevention is critical, stainless steel or specially coated screws may be a better option.

Unfortunately, without current, specific details on promotions or partnerships, I cannot provide an exact "A Little Extra Epoxy" coupon code here. However, I suggest visiting the official website of "A Little Extra Epoxy" or their social media profiles, as businesses often post discount codes or have sign-up offers for new customers there. Additionally, coupon websites and crafting forums might sometimes list relevant discount codes. Remember, ensure the code is valid, and check the expiration date and any specific terms related to the discount to make the most of your purchase.

Epoxy grout is known for its durability and resistance to stains and water damage, making it an excellent choice for areas exposed to moisture. Unlike traditional cement-based grout, epoxy grout doesn't crack or shrink over time, which is why some might consider skipping caulking when using it. However, despite these properties, caulking is still essential in certain areas. For instance, any change of plane in the tiling work—such as corners, edges, or where the tile meets another surface—should be caulked. This is because these areas are prone to movement and expansion, which can lead to cracking. Caulk is designed to be flexible and can absorb this movement, preventing damage. Therefore, even with the use of epoxy grout, caulking is necessary for ensuring the longevity and integrity of your tile work in specific areas.