There are cases where a Kenzot shirt does not have a washing mark, but this does not mean that it is not genuine. Some brands of clothing use different washing methods or materials and therefore do not require a care label.

To identify whether a Kenzot shirt is genuine, you can start from the following aspects:

1. Collar label: The collar label of a Kenzot shirt should be clear and detailed, with fonts and patterns. They should all be very clear, with no blur or offset.

2. Printing: The printing of the Kenzot shirt should be very clear, without blur or offset, and the printing color should be very bright, without fading.

3. Fabric: The fabric of Kenzot shirt should be soft, comfortable, breathable, feel very good, and the quality of the fabric should be very good, without pilling or fluffing.

4. Packaging: The packaging of Kenzot shirts should be very exquisite. The packaging boxes and bags should be exclusive to the brand, and there should also be labels and tags.

In short, to identify whether a Kenzot shirt is genuine, you need to carefully observe the details such as collar label, printing, fabric and packaging, and compare it with the brand's official website or specialty store. If you still have concerns, it is recommended that you consult brand officials or professionals.