Ouch, mine is solid vinyl so the cleaner is just about anything that cleans.
Unfortunately, many cleaners will destroy the finish on that suspected aluminum insert yours shows. Maybe use dishwashing soap if it is aluminum. Test somewhere inconspicuous.
If it's SS, no problem and use any cleaner which will do the job.
As far as preserving the cleaning job, I use :
Apply once or twice per year to keep it repelling water. Makes cleaning a breeze.