Engel Transit Slide Lock Question for the MT45F-U1

[SirCampalot]

Per Engel's website, both the TSL530 and TSL540 will fit the MT45 fridge. From what I have been able to gather, The TSL530 will fit both MT45 and MT35 models and the TSL540 is MT45 specific. Does anyone know what the differences are between the two?

Thanks in advance.