I have just upgraded my MSI Katana GF66 11UG RAM to 64GB with two of the sticks shown in the image. I checked prior and they are 100% compatible and my laptop
MSI KATANA GF66 11UE-1018XAE, Intel Core i7-11800H, RAM 16GB, 512GB SS – العالمية للحاسبات
MSI Katana GF66 11UC Intel 11th How to Replace Battery Disassembly - YouTube