Step 1
Download package, unzip it you will have 2 plugins.
Please install plugins as normal, then go to plugin manager for enabling those plugins.
Step 2
How to set up weight,prices for product:
Go to Virtuemart-> Product tab, choose Taxes & Calculation Rules, add new

- Calculation Rule name : fill "JMS weight" or what name you like
- Published: check on checkbox
- Description: descripotion
- Type of Arithmetic Operation : choose price you want to apply rules
- Math Operation: choose math operation will calculatator for price
- Currency: choose Currency
- Product Category: select cateogries you want to apply
JMS Weight parameters
Click "Add Weight Customize" for adding rules
Example 1: As image example above, when user buy 2 or 3 kgs of product, user will get discount $1 for each kg, when user buy 4 or 5 kgs of product, user will get discount $2 for each kg, and when user buy from 6 kg of product, user will get discount $3 for each kg. You have 3 rules:
- 1.Min:2, Max:0, Overwrite value: 1
- 1.Min:4, Max:0, Overwrite value: 2
- 1.Min:6, Max:0, Overwrite value: 3
Example 2: when user buy from 2 to 4 kg of products, user get discount $2 for each kg; when user buy from 6 to 8 kgs oft product, user get discount $3 for each kg; and when user buy from 10 kgs of products, user get discount is $4 for each kg. You will add 3 rules like below:
- 1.Min:2, Max:4, Overwrite value: 2
- 1.Min:6, Max:8, Overwrite value: 3
- 1.Min:10, Max:0, Overwrite value: 4
All products in categories( what you selected to apply rules) will auto update rules for price. For special product, please edit it, choose JMS weight as image below:

Go to Virtuemart-> Product tab, choose Custom fields, add new
Set name of new custom field is "JMS weight", choose type is plugins and set Select a plugin field is VMCustom- JMSheight
Edit a product, go to Custom field tab, choose Custom fields type is JMS weight, click save and enjoy.