Pinit RFI Spring Adaptor; 3/8" 26TPI - Male/Female SKU: SK-851-3/8 Lightweight spring, fits any standard mobile antenna with 3/8" 26TPI thread. Allows flexibility for low clearance such as car parks or overhanging trees. Login for pricing DESCRIPTION SPECIFICATIONS PDFS, DOWNLOADS & VIDEOS SK-851-3/8 Features: Lightweight spring which can be fitted to CD17, CD28, CD50 & CD51 stud mounted antennas.