A developer product, also referred to as a consumable, is an asset that may be bought more than once. Developer products are associated to places, and they are meant to be bought from inside games. There is no mechanism allowing a developer to know how many times a developer was brought, as it is the responsibility of a game developer using developer products to count this using the data store or data persistence. Developer products were first announced in a blog post about ROBLOX's Halloween game for 2013, which used consumables to sell in-game advantages. They were released later for certain developers in the same year. They were released for everyone February 28, 2014. A developer product can only be purchased once and used once unlike its predecessor, Game Passes. This allows developers to earn more cash and to allow them let their players to buy something without owning it.
A good exmple in how to use multiple developer products is here.