function Add Item

[Dan4ik]

Hello!
In version 1.x was implemented function "Add Item", I cant understand how this function is realize in version 2.0? or in 2.0 there is no such option?
PS: i need to realize such thing:
i have one kind of goods, but in several packages(different weight of goods), how client  can choose in frontend what package does he wants?

[attachment cleanup by admin]

[PRO]

custom fields are where there are now.

stockable variant, and child product