On the market, there are lots of cheap COB (chip on board) LEDs available. You could make them work for yourself, for example, make LED lights for working on your car, or taking pictures.
Some of them I bought several years ago:
On their back, I usually write something down, like specification (most V and A are measured by myself, some of them by the manufacturers) and price:
1. 30 W, 28-36 V, 0.9 A, 2800-2900 LM, $1.47
2. 50 W, 28-36 V, 1.5 A, 4600-4700 LM, $1.50
3. 100 W, 32-34 V, 3-3.5 A, 9000-10000 K, $4.90
4. 30 W, 28-36 V, 0.9 A, 2800-2900 LM, $1.47 (the same as #1)
5. 100 W, 28-36 V, 3 A, 8700-9000 LM, $1.75
6. 100 W, 28-36 V, R 28 V, 267 mA; G 33 V, 276 mA; B:32 V, 280 mA, $4.98
7. 20 W, R: 13 V, 139 mA; G: 18 V, 125 mA; B: 19 V, 128 mA
8. 50 W, R: 17 V, 279 mA; G: 24 V, 279 mA; B: 25 V, 264 mA, $2.33
9. 70 W, 12 V, $3.68, 5/5/2021
10. 50 W, AC, $1.5
11. Red, 12 V, 10W, 2/26/2021
12. Warm white, 12 V, 10 W, $2, 6/19/2020
13. Green, 12 V, 10W, 2/26/2021
14. Blue, 12 V, 10W, $2.00, 6/19/2020
15. Should be 12 V, RGB
16. Should be 12 V, RGB
To make LED lights, you need a power supply:
1. Power supply: 110 V AC to 36 V DC, around $10-30:
2. Power supply 110 V AC to 12 V DC, 5 A, for $10:
3. Power supply 110 V AC to 12 V DC, from HP server 900 W (used, $20) + adapter board ($16):
The LED lights:
1. 36 V, 100 W (please don't look it with naked eyes, I spoted it accidently, it took around 10 minutes to restore my vision):
2. 12 V (0.56 A, 6000 K, 20 inch long, $3.26 each):
LED lights at work:
1. 36 V, 100 W:
2. 12 V 6-7 W each:
