Since each piece of equipment is associated with a specific equipment type, these types need to be setup first. You just need to select a short equipment type code (i.e. ADAPJ, ADATRAIL, PJ1, etc. ) and a description.
This equipment type will also be used when setting up your line items (Products) or inventory for tickets and billing.
With the relationship between the line item to the equipment type, PJR can then provide the user with a list of actual equipment codes to select from when editing the ticket.