Buy a larger quantity and save X

[nghhbbtd]

Hello, 

I'm looking for an app or similar solution that will display on the product page comparing the price of two variants. 

For example, we sell a 1kg and 3kg option, so I'd like to display that the 3kg option is cheaper/better value. 

I've attached an image of what I'd like to do. If anyone has any app ideas, please let me know! 

Current website is https://www.horseherbs.co.uk/ however the theme is changing soon to Vision. 

Thank you