What is the driverless ac cob led chip？
A: Oh! Long time no see,my friend!!
B: Oh ,yes,I haven't seen you for half a year.
A: You look very excited, what happened to you?
B：Yes!!Good new！！I'm developing a light source accessory that is more convenient and safe to install.
A：What's this?
B: It's .........
（To be continued）