 NEP Electronics | CD21AA-BK | 2 | 50 | 1 | 2 @ $2.75, 50 @ $2.55, 100 @ $1.80, 500 @ $1.60 |
 BPD Electronics | CD21AA-BK | 3 | 50 | 3 | 1 @ $2.87 |
 Products For Automation | CD21AA-BK | 1 | 2374 | 1 | 1 @ $2.19 |
| Digi-Key | 15906048 | 5 | 1995 | 5 | 5 @ $2.41 |
 Radwell | CD21AA-BK | 9 | 2 | 9 | 1 @ $7.00 |
 Onlinecomponents.com | CD21AA-BK | 1 | 2 | 1 | 1 @ $3.22, 25 @ $3.03, 50 @ $2.63, 100 @ $1.95, 500 @ $1.70, 1000 @ $1.56 |
 Onlinecomponents.com | CD21AABK | 1 | 164 | | 1 @ $3.22, 25 @ $3.03, 50 @ $2.63, 100 @ $1.95, 500 @ $1.70, 1000 @ $1.56 |
| Master Electronics | CD21AABK | | 144 | | 1 @ $3.22, 25 @ $3.03, 50 @ $2.63, 100 @ $1.95, 500 @ $1.70, 1000 @ $1.56 |
| Electro Sonic | CD21AABK | 1 | 164 | | 1 @ $3.41, 25 @ $3.21, 50 @ $2.79, 100 @ $2.07, 500 @ $1.80, 1000 @ $1.65 |