[Tee tiong huat]

Many ppl dont know buying US weapons got 1 problem. You need to ask for permission.
They can switch off the GPS, your high tech weapons will be like a headless fly. 

US also fear their high tech weapons which they sold to other countries will be used to bomb their own ground.

China has learnt the lesson hard. This is why they built their own navigational system.

As T-72 crew Vlad, scrambled out of a nearby fox hole, where he had been warming his grimy hands seconds later, a skull-shaking explosion echoed across the valley and towards Bakhmut, as a US-supplied tank shell tore out of the gun barrel with a flash of orange, heading towards Russian positions on the opposite hillside.

Soviet-era tank T-72s are old tanks - this one's the same age as me," said Bogdan, a 55-year-old Ukrainian volunteer, turning to pat the huge, squat, Soviet-era machine behind him. "I used to drive one of these nearly 40 years ago - I can't believe I'm doing it again. But it works. It does the job.