Early suitcases were made of wood or other heavy materials, and with the popularity of air travel, the materials used in suitcases tended to be lighter, hard plastic or cloth. Most models also come with built-in small wheels, which can be easily pulled by a lever. After 2010, there were also suitcases with four small wheels, which can rotate 360 degrees and be easily pushed on flat ground without any effort. In addition, luggage can also be pided into hard shell luggage and soft shell luggage according to the outer shell. Hard shell luggage is more resistant to falling and is suitable for luggage that requires more protection. Soft shell suitcases are usually lighter in weight than hard shell suitcases and have more elastic capacity. However, the zipper position of a soft shell suitcase is more likely to explode due to too many objects inside. The size of luggage on the market is generally based on the size regulations of the carrier (hand luggage) and check-in box (cabin luggage) of the airline (International Air Transport Association). For example, Cathay Pacific stipulates that the maximum size of each piece of cabin luggage must be less than 158 centimeters, while the maximum size of each piece of hand luggage must be less than 56x36x23 centimeters

Function of testing report:

1. Project bidding: Issue authoritative third-party CMA/CNAS qualification report

2. Online e-commerce platform entry: Quality inspection report recognized by major e-commerce platforms

3. Used as a sales report: issuing legally effective testing reports to make consumers more confident

4. Papers and research: Provide professional personalized testing needs

5. Judicial services: providing scientific, fair, and accurate testing data

6. Industrial problem diagnosis: Verify the troubleshooting and correction of industrial production problems

100% inspection and testing process:

1. Telephone communication and confirmation of requirements

2. Recommend solutions and confirm quotations

3. Mail samples and arrange testing

4. Progress tracking and result feedback

5. Provide reports and after-sales service

6. If urgent or priority processing is required

Testing and testing characteristics:

1. The testing industry is fully covered, meeting different testing needs

2. Fully cover the laboratory and allocate localized testing nearby

3. Engineers provide one-on-one services to make testing more accurate

4. Free initial testing, with no testing fees charged

5. Self service order delivery for free on-site sampling

6. Short cycle, low cost, and attentive service

7. Possess authoritative qualifications such as CMA, CNAS, CAL, etc

8. The testing report is authoritative and effective, and is generally used in China