Seibu 4000 series

The 4000 series trains were built between 1988 and 1992 by combining electrical equipment from former 101 series EMUs with new steel bodies.^[1] The trains are finished in a livery of ivory white with blue, red, and green stripes along the waist line, the team colours of the Saitama Seibu Lions baseball team.^[1] The driving cabs have a similar configuration to the earlier 101 series and 2000 series EMUs, with a left-hand master controller and right-hand brake control.^[1]

• 
  The driving cab console

The fleet of four-car trains is primarily used on all-stations driver only operation "Local" services on the Seibu Chichibu Line between Hannō and Seibu Chichibu, but the trains are also used as eight-car formations on through "Rapid Express" train services from Ikebukuro on the Seibu Ikebukuro Line to Mitsumineguchi and Nagatoro on the Chichibu Main Line.^[1] These trains divide and couple at Yokoze, with separate portions for Mitsumineguchi and Nagatoro.^[1]

As of 1 April 2016^[update], the fleet consists of twelve four-car sets, numbered 4001 to 4023, based at Musashigaoka depot.^[2]

Sets are formed as shown below with two motored ("M") cars and two non-powered driving trailer ("Tc") cars, and the Tc1 car at the southern (Ikebukuro) end.^[2]

The M1 car is fitted with two single-arm pantographs (originally lozenge-type pantographs).^[1][2]

• 
  Car 4002 of set 4001 in May 2006
• 
  Car 4001 of set 4001 in May 2006

Seating mainly consists of fixed 4-person facing seating bays, with longitudinal bench seating next to the doorways.^[1] The Tc1 car has a toilet.^[2]

• 
  Train interior view
• 
  4-person seating bay
• 
  Toilet and priority seating
• 
  Wheelchair space

The first train entered service in 1988, with twelve four-car sets built by 1992.^[1] The fleet was refurbished in 2002 for use on wanman driver only operation services on the Seibu Chichibu Line. Modifications included the addition of automatic passenger announcements.^[1]

One four-car set was modified from set 4009^[3] into a tourist train called the Fifty-two Seats of Happiness (52席の至福, Gojūni seki no shifuku) for use on services operating between Seibu Shinjuku and Ikebukuro in Tokyo and Seibu Chichibu and Hon-Kawagoe in Saitama Prefecture, entering service from 17 April 2016.^[4] The interior and exterior design of the train was overseen by architect Kengo Kuma.^[5]

The automated on-board passenger announcements in Japanese use the voice of TV presenter Tomomi Kuno [ja], and the melody chimes accompanying the announcements were created by musician Minoru Mukaiya, who was formerly the keyboard player in the group Casiopea.^[3]

The train is formed as shown below, with car 1 at the Tokyo (southern) end.^[2][6]

• 
  Car 4009 (car 1) with spring motif
• 
  Car 4109 (car 2) with summer motif
• 
  Car 4110 (car 3) with autumn motif
• 
  Car 4010 (car 4) with winter motif