Controllers can look alike from the front while having different ports, buttons and phone clamps. A cover that slips over the body may still interfere with a control you use on every flight.
Match the model first
Read the model name on the controller itself and compare it with the accessory listing. Check photos of the top and bottom edges as well as the front. A photo of the drone alone does not identify the controller bundled with it.
Check the fit before flying
With the controller powered off, fit the cover and move the sticks through their full range. Open the clamp, connect your usual cable and check that the cover does not press a button. If you have to pull the cover aside to plug in the cable, choose a better fit.