This formation has been almost completely worn away by subsequent impacts, leaving little more than a crater-riddled depression in the surface. There is an equally worn crater lying across the northern rim, and Crommelin X is attached to the outward-bulging northwest perimeter. The largest of the craterlets within the interior form a pair near the southern rim. There is a slight central peak, consisting of little more than a low rise in the surface.
By convention these features are identified on Lunar maps by placing the letter on the side of the crater midpoint that is closest to Crommelin.
Menzel, D. H.; Minnaert, M.; Levin, B.; Dollfus, A.; Bell, B. (1971). "Report on Lunar Nomenclature by the Working Group of Commission 17 of the IAU". Space Science Reviews. 12 (2): 136–186. Bibcode:1971SSRv...12..136M. doi:10.1007/BF00171763.