These are belheli skylinker 40A esc with bec 5v 3A.
Pre sold battery connector and esc connectors
High quality powerful esc Belheli version better than simonk
It gaves very quick throttle response.
Current 40amp Max current 55amp
Voltage : 2-3S LiPo BEC
output: linear mode: 5V, 3A
Output plug: 3.5mm connector
Package Included 1x 40amp esc