how to generate the buy x get y coupon for the custom fields

Dear Support,

I would like to check how can i able to use the buy x get y feature for the items are having the custom fields. Like to say as example below.

-- The product name "ABC123" having the pack sizes as the custom fields. Which is 5kgs, 10kgs, 20kgs, 30kgs.
-- Each packs had the different values while the customers/members by chosen or checkout time.
-- And i wants to do the promotion to say, when the customer choose 5Kgs as two i given away as 1 5Kgs pack.
-- And when the customer choose 10Kgs then 1 pack of 5Kgs and there is no promo for 20kgs and 30kgs.
-- I did created at the coupon as buy x get y feature.
-- But then, noted that when the customer choose 10Kgs or 20Kgs or 30Kgs as 2 packs also the system giving as 10kgs as 3packs or 20kgs as 3packs or 30kgs as 3packs instead of 5kgs.
-- is that possible to control the packs size at the coupon module? Which is these packs are maintained by virtuemart 3.0.12 custom fields.

Can assist on this?

thanks.
Madhu

Hello,

Unfortunately it is not possible create a coupon on a specific custom field. So no way to do what you want, unless they had their own separate product ids.