<p> Plastic isn't just made of plastic, it also contains vinyl, nylon, silicone and rubber. Each type of plastic has its own specifications and benefits. </p><ul><li>Consider using <strong>rubber caps and plugs</strong> if you're looking for flexible caps that are extremely tolerant to heat (up to 315 degrees Celsius).</li><li><strong>Silicone caps and plugs</strong> are medium resistant to heat (up to 246 degrees Celsius), but are very flexible and providing a thight seal, so useful as noise inhibitors.</li><li><strong>Vinyl caps and plugs </strong>are the most economical choice if heat resistance is not crucial. </li><li><strong>Nylon caps and plugs</strong> are strong and suitable for a range of base materials. </li><li>Consider <strong>metal caps and plugs </strong>if extra durability and strenght are needed such as harsh environmental conditions. </li></ul>