What are the larger security service companies in Shenzhen?

Blue water special guard is rubbish. I have been there before. Don't advertise with the navy! All kinds of routines, as soon as they recruit people, they will be dragged to the night shift, and then a security suit will deduct hundreds of wages! The living place is even worse, and several people sleep in the same bed! Speaking of food, in fact, sometimes employees don't give working meals and have to pay for themselves! 12 hour! Tired as a dog. I still have to pay a month's salary, and leaving my job is also very troublesome. Still have to find all kinds of excuses to delay! Even if I let you go, I won't settle my salary!