This EH series is interchangeable with PARKER H SERIES, PARKER IH SERIES, SNAP-TITE H SERIES, SNAP-TITE IH SERIES, DIXON V SERIES, FASTER TNV SERIES, FASTER TNL SERIES, DNP PNV1 SERIES, DNP PNO1 SERIES and STUCCHI SH SERIES. Steel Product. 105 series couplings are commonly used in US market as an alternative to standard series. Their valves have been designed to help flow and to allow connection with 106 parts (free flow) same series. Carbon Steel.