This is the top of the range 4in1 ESC from Spedix.  If you were a fan of the GS40, the GS45 is a worthy replacement.  This ESC is designed to handle all the abuse you can trow at it with the bigger heatsink which helps with cooling and protection.

Key Features

• 2-6S compatible, 45A Continuous output (55A Peak)
• Bat or 10V output to power other gear
• BLheli32 with ESC telemetry support and Current sensor.
• Super low profile (1.6mm with heatsync)
• Delicate parts moved far away from standoff mounting holes for better protection
• Silicone ring inserts can insulate standoffs and ESC, and prevent impact of standoffs on PCB and electronic parts during crash.
• Smaller square footprint with motor connectors compatible with just about any frame out there.
• Includes 3 cables to fit various flight controller amongst other accessories.

Specifications

• Input:3-6 Cell LiPo
• Continuous Current: 45A
• Burst Current: 55A≤10S
• BEC:10V/2A
• Current Detection: Yes
• Firmware: BLHeli_32
• Dimensions: 40.5x42x6.5mm
• Mount holes: 30.5×30.5mm
• Diameter of Mount holes: 3mm
• Weight：17g”