| Disaggregation of Revenue | The following table presents our revenue disaggregated by Market Segments as follows: 
The following table presents our revenue disaggregated by Product Lines as follows:
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | Six Months Ended |  | Three Months Ended |  
| (In thousands) |  | July 3, 2021 |  | June 27, 2020 |  | July 3, 2021 |  | June 27, 2020 |  
| Aerospace Segment |  |  |  |  |  |  |  |  |  
| Commercial Transport |  | $ | 86,001 |  |  | $ | 170,323 |  |  | $ | 47,793 |  |  | $ | 67,548 |  |  
| Military |  | 37,783 |  |  | 32,165 |  |  | 16,801 |  |  | 14,052 |  |  
| Business Jet |  | 29,022 |  |  | 30,548 |  |  | 14,994 |  |  | 15,542 |  |  
| Other |  | 17,830 |  |  | 10,607 |  |  | 9,632 |  |  | 5,431 |  |  
| Aerospace Total |  | 170,636 |  |  | 243,643 |  |  | 89,220 |  |  | 102,573 |  |  
|  |  |  |  |  |  |  |  |  |  
| Test Systems Segment |  |  |  |  |  |  |  |  |  
| Semiconductor |  | — |  |  | 2,822 |  |  | — |  |  | 1,188 |  |  
| Aerospace & Defense |  | 46,379 |  |  | 34,813 |  |  | 21,938 |  |  | 19,933 |  |  
| Test Systems Total |  | 46,379 |  |  | 37,635 |  |  | 21,938 |  |  | 21,121 |  |  
|  |  |  |  |  |  |  |  |  |  
| Total |  | $ | 217,015 |  |  | $ | 281,278 |  |  | $ | 111,158 |  |  | $ | 123,694 |  |  
|  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  |  
|  |  | Six Months Ended |  | Three Months Ended |  
| (In thousands) |  | July 3, 2021 |  | June 27, 2020 |  | July 3, 2021 |  | June 27, 2020 |  
| Aerospace Segment |  |  |  |  |  |  |  |  |  
| Electrical Power & Motion |  | $ | 64,092 |  |  | $ | 116,019 |  |  | $ | 34,748 |  |  | $ | 46,563 |  |  
| Lighting & Safety |  | 51,468 |  |  | 65,653 |  |  | 24,368 |  |  | 27,731 |  |  
| Avionics |  | 32,864 |  |  | 41,277 |  |  | 18,021 |  |  | 19,134 |  |  
| Systems Certification |  | 1,838 |  |  | 4,991 |  |  | 960 |  |  | 1,660 |  |  
| Structures |  | 2,544 |  |  | 5,096 |  |  | 1,491 |  |  | 2,054 |  |  
| Other |  | 17,830 |  |  | 10,607 |  |  | 9,632 |  |  | 5,431 |  |  
| Aerospace Total |  | 170,636 |  |  | 243,643 |  |  | 89,220 |  |  | 102,573 |  |  
|  |  |  |  |  |  |  |  |  |  
| Test Systems |  | 46,379 |  |  | 37,635 |  |  | 21,938 |  |  | 21,121 |  |  
|  |  |  |  |  |  |  |  |  |  
| Total |  | $ | 217,015 |  |  | $ | 281,278 |  |  | $ | 111,158 |  |  | $ | 123,694 |  |  |