* * * Different sizes. **5a Macrobrachium nipponense is bigger than 4a Macrobrachium nipponense. According to the standard that the number on the box usually represents the number of frozen shrimps with a weight of 1 kg, for example, 30/40 means that there are about 30-40 frozen shrimps with a weight of 1 kg, it can be known that the freshwater shrimps in 5a are larger than those in 4a.
* * * The quantity is different. * * There are generally about 80- 100 frozen shrimps with a weight of 4 kg and a specification of 40/50, and the number of freshwater shrimps in 5a is less than that in 4a.
For different people, the definition and acceptance of size may be different, and you can choose according to your personal preferences.