Donating scientific equipment to ONAMET

We are a US scientific group working with ONAMET. We are going to donate some meteorological equipment to ONAMET for their use. We want to avoid paying customs duties/taxes when we ship it to the DR. We are going to use Fed Ex to ship the equipment from the USA.

Can anyone provide advice on the best way to accomplish this? Is there a standard donation form we could use?

Thanks in advance.