Service Item is the term used by MechanicDesk to describe the workshop's industry. For example automobiles, boats, buses, trucks, etc. It could even be parts, machines. Whatever you build or service, that's your service attribute. 

MechanicDesk defaults the Service Item to Vehicles but you can change this to what suits you here:

A Service Item has many attributes associated with it. For example if your workshop deals with cars, you will be interested in the registration number, VIN, make, model, cylinder number, gearbox model, etc. For a workshop that deals with trailers, they will most likely be interested in trailer numbers, trailer models, etc. These are all examples of service attributes and you can choose which ones show up on the same screen:

Now that you've set up your service item and service item attributes, lets move on. Please click here.