Thomas & Betts 5254GRX 1 90 DEG GR LT

Yes. The 5254GRX is a 1 inch trade size 90 degree grounding connector for liquidtight flexible metal conduit, so it lands on a box or enclosure at a right angle rather than straight in. Use it where the conduit run has to turn immediately at the enclosure and there is no room to sweep the flex.

GR means it is a grounding type connector. It has a provision for terminating an equipment grounding conductor at the fitting itself, so the ground can be landed at the connector instead of carried past it on a separate external jumper. Bonding still has to satisfy whatever your inspector requires for the circuit, but the fitting is the grounding version rather than the standard non-grounding 90.

Malleable iron. That is the heavier-duty body material for liquidtight connectors, as opposed to die cast zinc, and it is what specifiers usually call for in industrial and wet-location work where the fitting takes mechanical abuse.

That is exactly what it is for. A 90 degree connector makes the turn at the enclosure in one fitting, which saves the space a straight connector plus a conduit bend would need. Pick the straight version instead when the flex enters the box on axis and you have clearance behind it; pick the 90 when the conduit has to break immediately off the hub. Either way, match the 1 inch trade size to your liquidtight flex.