成田エクスプレス
The two 3-car sets were converted from former 253 series 3-car EMU sets Ne107 and Ne108, purchased from JR East in 2010 following their withdrawal from "Narita Express" services. They underwent modifications for "wanman" ("one man") driver only operation at Tokyu Car's Yokohama factory before being moved to the Nagano Electric Railway in December 2010 for final repainting.