It ultimately depends on personal preference and what you would use more often. If you find yourself needing a pen frequently, then a pen would be the more practical choice. However, if you are someone who frequently loses or misplaces keys, then a keychain might be the more useful option. Both items can be functional and stylish accessories, so it's really a matter of what you would get the most use out of. **

Without further information or context, it is difficult to determine if the keychain is broken. If you can provide more details about the issue with the keychain, such as a description of the damage or malfunction, I would be happy to help assess the situation. **

To mount a compass attachment onto a compass, first ensure that the attachment is compatible with the specific model of compass. Then, carefully align the attachment with the designated mounting area on the compass. Depending on the design, you may need to use screws, adhesive, or other fastening methods to secure the attachment in place. It's important to follow the manufacturer's instructions and make sure the attachment is securely mounted to ensure accurate readings. **

A car keychain is a small decorative item that is attached to a set of car keys. It is often used to personalize and accessorize the keys, and can come in various designs, shapes, and materials. Some keychains may also have additional functions, such as a mini flashlight or a bottle opener. Overall, a car keychain serves as a practical and stylish way to keep track of and identify one's car keys. **

This keychain is a multi-functional tool that can perform a variety of tasks. It includes a bottle opener, a screwdriver, a wrench, and a ruler, making it useful for everyday tasks and emergencies. Its compact size and lightweight design make it easy to carry around and have on hand whenever needed. Overall, this keychain is a versatile and practical tool for anyone to have. **

The compass was invented by the Chinese during the Han Dynasty, around the 2nd century BC. **

Without more information or context, it is impossible to determine if the compass is broken. To determine if the compass is broken, one would need to check if the needle is moving freely, if there are any visible damages, or if it is functioning properly when compared to a known direction. If the compass is not pointing north or is not responding correctly, it may be broken and in need of repair or replacement. **

You can search for a compass at outdoor recreation stores, camping supply stores, or online retailers. Look for a compass that is durable, accurate, and easy to read. Consider features such as a liquid-filled capsule for stability, a clear base plate for map reading, and a declination adjustment for precise navigation. Make sure to choose a compass that suits your specific needs, whether it's for hiking, backpacking, orienteering, or general outdoor use. **