Danfoss / Eaton Gear (SLIP FIT)

That's right. Slip fit means there's no keyed connection involved. It slides onto the drive shaft and holds its position through the fit itself, which makes swapping it out or dropping it in a whole lot easier than dealing with keyed setups. That's why these show up so often in tandem pump arrangements or accessory drive configs where you might be adding a secondary pump or motor to the primary shaft.