In the capacity design of automobile watering can, we need to pay attention to the following aspects:

1. Usage scenario: Determine the capacity according to the main usage scenario of the automobile watering can. If it is mainly used for daily cleaning vehicles, the general capacity is about 1-2 liters to meet the demand; If you need to clean a large area or use it for a long time, you can choose a larger capacity watering can.

2. Portable: Consider whether the capacity of the watering can is suitable for carrying. Excessive capacity will increase the weight and make it inconvenient to carry; If the capacity is too small, it may not meet the cleaning requirements. Need to strike a balance between capacity and portability.

3. Continuous use time: According to the user's habits and needs, determine whether the capacity of the watering can meet the time requirement of continuous use. If the capacity is too small, water may need to be added frequently, which will affect the use efficiency; Excessive capacity may increase unnecessary weight.

4. Water storage space: Considering the storage space inside the vehicle or the trunk, choose the appropriate capacity design to ensure that the watering can be stored and carried conveniently.

5. User demand: Determine the capacity of the watering can according to the user's personal needs and habits. Some users may prefer a compact and lightweight design, while others may value the size of the capacity.

6. Frequently adding water frequency: According to the user's usage frequency and habits, determine whether the capacity of the watering can needs to be frequently added with water. Adding water too frequently may affect the user's experience.

To sum up, in the capacity design of automobile watering can, factors such as usage scene, portability, continuous use time, water storage space, user's demand and water adding frequency should be considered to ensure that the capacity can meet the user's demand and improve the practicality and convenience of watering can.