Rail Mounting.
For CDQ2, CDQP2, CDBQ2, CDLQ, CDQ2X, CDQ2Y, CDQM, RDQ, RDLQ, C55, NCQ8, RZQ, CXT, MK, MK2, RSDQ, MDU, MDLU, CE1.
For MHF2, MHZ2, MHZJ2, MHZL2, MHL2, MDHR2, MDHR3, MHK2, MHS2, MHS3, MHSJ3, MHSH3, MHSL3, MHS4, MHC2, MHT2, MHY2, MHW2, MRHQ