The tax treatment is affected by the donee's use of the inventory and the type of charity to which it is given.
There is a difference in donating inventory that is to be resold by the charity in order to have the cash and donating inventory to a charity which will use it in the conduct of its charitable purpose.
In the case where the non-profit org is going to sell the property, you are able to deduct your basis in the inventory.
However, when you contribute the property to a charity which (in general) functions to provide relief to sick or the poor, you can deduct your basis in the inventory plus 1/2 of the difference between the retail price and your basis. Furthermore, the charity must keep the inventory and use it in the furtherence of its exempt function.
For example, I had a furniture store contribute matresses to a shelter for homeless men. The matresses cost $100 each and sold for $150. Their deduction was for $125 (100 + (.5*(150-100)).
If the amount of the donation is significant, you need to get a copy of the charity's "exemption letter" from the IRS. This is the letter from the IRS stating that the organization has received exemption from federal income taxes.
You also need a representation from the organization that the donated items will be used by the charity and not resold. You also need to get a representation that the items will be used in providing services consistent with the purpose for which they received their exemption.
Finally, I would ask a CPA or Tax Attorney to review your facts and give you advice specific to your particular facts and circumstances.