Dimensions: Inside (dia): 0.625" inside depth: 1.250", overall ht: 2.125", overall (dia): 1.375". Fits the Following: AKG C451, C452, C460, CK1,CK2, D109,D110. Audio-Technica ATM75. Beyer MC721, MC723. E.V. 649B. Schoeps CM-U,CMC,MK Series. Shure 570S,572 and others with up to a .75" outside diameter.