What Richelle has given you here is basically the Websters Dictionary definition of contract. Which is correct but is too broad for your use.
You need to contact a contractual lawyer if you want to cover your behind 100% , however these guys cost $$$. If you have it great. If not come up with something similar to this. You should really put out a Registration of Interest to various manufacturers before settling on anyone. The ROI should cover
(1) What you want made and how many
(2) Materials to be used (you Stipulate)
(3) Manufacturing standards ie to USA standards Or Aust Standards
(4) Quality Control (company to demonstrate previous works)
(5) Delivery time frame (how long they have to make)
(6) Penalty clauses for inferior products or delivery not on time
You need to think through this carefully as a ROI is designed to get your item made to your requested standards and processes and with the required quality you expect.
Once you have an ROI send it out to however many manufacturers you wish so they can submit their offers to you. If you are looking at a country like China you can approach the Chinese Trade Commission for assistance in shortlisting prospective tenderers or which ever country you choose as they all have Trade Commissions designed to help their conutries companies export goods and services to the world.
Hope this helps