There are two families of Ultimaker printers: the Ultimaker Original series and the Ultimaker 2 series. In both, there are optional upgrades and add-ons. If you are not the original owner of the machine OR if you have added any upgrades, please look at the upgrade options to determine if/how the machine was modified. Knowing what machine and what upgrades you have will help tech support and customer service ensure you get the correct information and parts.
Ultimaker Original Series-
The Ultimaker Original and Original + are both wooden DIY kits.
The Ultimaker Original (UMO)- This model does not have a heated bed. It has an acrylic plate that is usually covered in blue tape to help filament adhere.
The Ultimaker Original + (UMO+)- This model has a heated bed and a white electronics board.
The Ultimaker Original with Heated Bed Upgrade- This is not the same as a UMO+. The UMO with the upgrade will have the heated bed but will still use the UMO electronics board which is green.
Ultimaker 2 Series-
The Ultimaker 2 machines are all fully-assembled. The frame is made of Dibond (polyethylene between two pieces of aluminum) as opposed to the wood of the original. One of the key differences between the Ultimaker 2 models is size. If an Extrusion Upgrade has been installed, the only way to know the model of the machine is by the serial number.
The Ultimaker 2 (UM2)- This is the first model released in the Ultimaker 2 series. Of the three sizes it is the middle size. It's roughly cube-shaped, sitting at approximately 14" in each direction. Serial numbers begin: UM2A, UM2B, or UM2C
The Ultimaker 2 Extended (UM2X)- This model is taller than the UM2 though it has the same footprint. Serial numbers begin UM2XTD
The Ultimaker 2Go (UM2Go)- This model is a miniature version of the UM2. While the mechanics of the printer are the same, this model does not have a heated bed.
The Ultimaker 2+ (UM2+)- This model comes with an Olsson block installed in the hot end. The feeder on this model works with a geared assembly and is white.
The Ultimaker 2 Extended + (UM2X+)- This model is the taller version of the UM2+.
Olsson Block Upgrade- An Olsson block can be fitted into the hot end of the UM2, UM2X, and the UM2Go. One of those models with an Olsson upgrade will still have a black feeder assembly.
Extrusion Upgrade Kit- This kit can be added to a UM2 or UM2X to give it the hot end and feeder of a 2+. The only way to know if you have a UM2 or a UM2+ is the serial number as the kit contains a + sticker to add to the frame.