From Pub 526
Deductions of Less Than $250
If you make any noncash contribution, you must get and keep a receipt from the charitable organization showing:
The name of the charitable organization,
The date and location of the charitable contribution, and
A reasonably detailed description of the property.
A letter or other written communication from the charitable organization acknowledging receipt of the contribution and containing the information in (1), (2), and (3) will serve as a receipt.
You are not required to have a receipt where it is impractical to get one (for example, if you leave property at a charity's unattended drop site).
