rinzai

First let me say: I am the owner, not the designer or tech person, of the website: rinzaismarket.com As far as I know he used php & java script as the coding language in WordPress. We have “The Cart Press” (TCP) as our shopping cart within WordPress.
Two examples of products with drop down menus that I’d like to have starting from small to large sizes would be:
http://rinzaismarket.com/product/extinguish/
and: http://rinzaismarket.com/product/rinzais-market-adrenal-tonic/
According to my web designer The Cart Press does not have a plug in that would enable the products to be listed from smallest to largest.
Thank you for your help. It’s been an issue for a long time.