Please read the following table in Markdown format and then answer the question according to the table. Table cells in one row are seperated by '|', and different rows are seperated by '
'.

Table:
| Year | IBM Model Number | Name | Processor | Bus | HD Interface | Case | Notes |
| --- | --- | --- | --- | --- | --- | --- | --- |
| 1987 | 8525-001 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Monochrome display | Single disk drive |
| 1987 | 8525-004 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Color display | Single disk drive |
| 1987 | 8525-G01 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Monochrome display | Single disk drive, enhanced keyboard |
| 1987 | 8525-G04 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Color display | Single disk drive, enhanced keyboard |
|  | 8525-101 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Monochrome display | Single disk drive |
|  | 8525-104 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Color display | Single disk drive |
| 1988 | 8525-L01 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Monochrome display | Single disk drive, token-ring network adapter |
| 1988 | 8525-L04 | Model 25 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Color display | Single disk drive, token-ring network adapter |
| 1987 | 8525-C02 | Model 25 Collegiate | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Monochrome display | Two disk drives |
| 1987 | 8525-C05 | Model 25 Collegiate | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Color display | Two disk drives |
| 1987 | 8525-K02 | Model 25 Collegiate | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Monochrome display | Two disk drives, enhanced keyboard |
| 1987 | 8525-K05 | Model 25 Collegiate | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop with integrated Color display | Two disk drives, enhanced keyboard |
| 1990 | 8525-006 | Model 25 286 | 10 MHz Intel 286 | ISA 16 bit |  | Desktop with integrated Color display | Single HD disk drive |
| 1990 | 8525-036 | Model 25 286 | 10 MHz Intel 286 | ISA 16 bit | ST-506, 30MB drive | Desktop with integrated Color display | Single HD disk drive |
| 1990 | 8525-G06 | Model 25 286 | 10 MHz Intel 286 | ISA 16 bit |  | Desktop with integrated Color display | Single HD disk drive, enhanced keyboard |
| 1990 | 8525-G36 | Model 25 286 | 10 MHz Intel 286 | ISA 16 bit | ST-506, 30MB drive | Desktop with integrated Color display | Single HD disk drive, enhanced keyboard |
| 1992 | 8525-K00 | Model 25 SX | 16 MHz Intel 386 SX | ISA 16 bit |  | Desktop with integrated Color display | Single HD disk drive |
| 1992 | 8525-K01 | Model 25 SX | 16 MHz Intel 386 SX | ISA 16 bit |  | Desktop with integrated Color display | Single HD disk drive, Ethernet network adapter |
| 1992 | 8525-L02 | Model 25 SX | 16 MHz Intel 386 SX | ISA 16 bit |  | Desktop with integrated Color display | Single HD disk drive, Token-ring network adapter |
| 1989 | 8530-001 | Model 30 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop | Single disk drive |
| 1987 | 8530-002 | Model 30 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop | Two disk drives |
| 1987 | 8530-021 | Model 30 | 8 MHz Intel 8086 | ISA 8 bit | WDI-325Q, 20MB, ESDI | Desktop | Single disk drives |
| 1988 | 8530-E01 | Model 30 286 | 10 MHz Intel 286 | ISA 16 bit |  | Desktop | Single HD disk drive |
| 1988 | 8530-E21 | Model 30 286 | 10 MHz Intel 286 | ISA 16 bit | ESDI, 20MB | Desktop | Single HD disk drive |
| 1989 | 8530-E31 | Model 30 286 | 10 MHz Intel 286 | ISA 16 bit | ESDI, 30MB | Desktop | Single HD disk drive |
| 1991 | 8530-E41 | Model 30 286 | 10 MHz Intel 286 | ISA 16 bit | ESDI, 45MB | Desktop | Single HD disk drive |
| 1987 | 8530-R02 | Model 30 | 8 MHz Intel 8086 | ISA 8 bit |  | Desktop, intelligent financial workstation | Two disk drives, 4700 host support |
| 1987 | 8530-R21 | Model 30 | 8 MHz Intel 8086 | ISA 8 bit | ST-506, 20MB | Desktop, intelligent financial workstation | Single disk drives, 4700 host support |
| 1988 | 8530-E0R | Model 30 286 | 10 MHz Intel 286 | ISA 16 bit |  | Desktop, intelligent financial workstation | Single HD disk drive, 4700 host support |
| 1988 | 8530-E2R | Model 30 286 | 10 MHz Intel 286 | ISA 16 bit | ESDI, 20MB | Desktop, intelligent financial workstation | Single HD disk drive, 4700 host support |
| 1987 | 8550-021 | 50 | Intel 80286 | MCA 16 bit |  | desktop |  |
| 1987 | 8560 | 60 | Intel 80286 | MCA 16 bit | MFM or ESDI | tower |  |
| 1987 | 8580 | 80 | Intel 80386 DX | MCA 32 bit | MFM or ESDI | tower |  |
| 1988 | 8550-031, 8550-061 | 50 Z | Intel 80286 | MCA 16 bit |  | desktop |  |
| 1988 | 8570 | 70 | Intel 80386 DX | MCA 32 bit |  | desktop |  |
| 1989 | 8555 | 55 SX | Intel 80386 SX | MCA 16 bit | ESDI | desktop |  |
| 1989 | 8570 | 70 | Intel 80386 DX, Intel 80486 | MCA 32 bit |  | desktop |  |
| 1989 | 8573-031 | P70 386 | Intel 80386 DX | MCA 32 bit |  | portable | 2 MCA slots, one full length, one half length. |
| 1990 | 8573 | P75 486 | Intel 80486 | MCA 32 bit | SCSI | portable | 4 MCA slots, two full length, two half length. |
| 1990 | 8580 | 80 | Intel 80386 DX | MCA 32 bit | SCSI | tower |  |
| 1990 | 8556 | 56 SX | Intel 80386 SX | MCA 16 bit |  | desktop |  |
| 1990 | 8565 | 65 SX | Intel 80386 SX | MCA 16 bit | SCSI | tower |  |
| 1990 | 8590 | 90 XP 486 | Intel 80486 | MCA 32 bit | SCSI | desktop |  |
| 1990 | 8595 | 95 XP 486 | Intel 80486 | MCA 32 bit | SCSI | tower |  |
| 1991 | 8540 | 40 SX | Intel 80386 SX | ISA 16 bit |  | desktop |  |
| 1991 | 8557 | 57 SX | Intel 80386 SX | MCA 16 bit | SCSI | desktop |  |
| 1991 | 8570 | 70 | Intel 80386 DX, Intel 80486 | MCA 32 bit |  | desktop |  |
Question:
which model was the first portable device?
Answer:
8573-031