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741 LEGO Trains 12 V Transformer thumbnail image

741 LEGO Trains 12 V Transformer
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741 LEGO Trains 12 V Transformer
  • 12 V Transformer thumbnail
  • 12 V Transformer thumbnail
  • 12 V Transformer thumbnail

LEGO 741 12 V Transformer is a vintage Trains set from 1974 valued at $144 for new and sealed sets, up 621% from an original retail price of $19.99. Annual appreciation has averaged 5.10% since release. Used copies are valued between $12 and $14 depending on condition.

Set Value (New/Sealed)

This chart represents the current new/sealed value of the set 12 V Transformer since December 2018. High accuracy
LEGO 741-1 12 V Transformer is a Trains 4.5V / 12V set released in 1974, containing 1 piece. This 220V AC version was designed for European markets and supplied power to the 12V LEGO train system of the era. It was part of the classic 4.5V/12V trains lineup and was succeeded in 1980 by the 7864 Transformer / Speed Controller 12V.

A new and sealed 12 V Transformer is currently valued at around $144, with annual growth of approximately 5%. The average used price is $12 for those in good overall condition. Based on current trends, this set could be valued near $151 within the next year. New and sealed listings currently range from $114 to $115.
All regions

For Sale (New/Sealed)

 (IT) 741 12V Transformer for 220V Pack 1974 Rare New Old Stock#HI $114.77
-20.3%
All regions

For Sale (Used)

 (DE) Used - - no box $12.68
(DE) Used - Lego 12V TRAIN Railway 741 Transformer Remote Control BLUE 2ND CHOICE
$13.95

Related Sets

7864 Transformer / Speed Controller 12 V

Theme / Subtheme Trains / 4.5V / 12V
Year 1980
Pieces 33
Availability Retired
7864 LEGO Trains Transformer / Speed Controller 12 V
Retail $65.99
Value $159.55
Growth  +141.8%
Annual growth 3.5%

740-2 12V Transformer for 220V Pack

Theme / Subtheme Trains / 12V
Year 1969
Pieces 1
Availability Retired
740-2 LEGO Trains 12V Transformer for 220V Pack
Retail $12.50
Value $44.91
Growth  +259.3%
Annual growth 2.3%

Sets in Trains / 4.5V / 12V

725-2 Freight Train Set

Theme / Subtheme Trains / 4.5V / 12V
Year 1974
Pieces 425
Availability Retired
725-2 LEGO Freight Train Set
Retail $25.50

182 Train Set with Motor

Theme / Subtheme Trains / 4.5V / 12V
Year 1975
Pieces 369
Availability Retired
182 LEGO Train Set with Motor
Retail $19.99
Value $1,375.26
Growth  +6779.7%
Annual growth 8.7%

148 Central Station

Theme / Subtheme Trains / 4.5V / 12V
Year 1975
Pieces / Minifigs 293 / 5
Availability Retired
148 LEGO Trains Central Station
Retail $19.99
Value $906.62
Growth  +4435.4%
Annual growth 7.8%

723-2 Diesel Locomotive with DB Sticker

Theme / Subtheme Trains / 4.5V / 12V
Year 1974
Pieces 98
Availability Retired
723-2 LEGO Trains Diesel Locomotive with DB Sticker
Retail $8.50
Value $450.77
Growth  +5203.2%
Annual growth 8.2%

133 Locomotive

Theme / Subtheme Trains / 4.5V / 12V
Year 1975
Pieces 87
Availability Retired
133 LEGO Trains Locomotive
Retail $2.89
Value $750.57
Growth  +25871.3%
Annual growth 11.5%

134 Mobile Crane and Wagon

Theme / Subtheme Trains / 4.5V / 12V
Year 1975
Pieces 86
Availability Retired
134 LEGO Trains Mobile Crane and Wagon
Retail $2.49
Value $428.02
Growth  +17089.6%
Annual growth 4.7%

136 Tanker Wagon

Theme / Subtheme Trains / 4.5V / 12V
Year 1975
Pieces 83
Availability Retired
136 LEGO Trains Tanker Wagon
Retail $1.89
Value $210.57
Growth  +11041.3%
Annual growth 9.6%

137-2 Passenger Sleeping Car

Theme / Subtheme Trains / 4.5V / 12V
Year 1975
Pieces 82
Availability Retired
137-2 LEGO Trains Passenger Sleeping Car
Retail $1.89
Value $321.56
Growth  +16913.8%
Annual growth 10.6%

755 Left and Right Points

Theme / Subtheme Trains / 4.5V / 12V
Year 1974
Pieces 12
Availability Retired
755 LEGO Trains Left and Right Points
Retail $11.99
Value $27.40
Growth  +128.5%
Annual growth 1.6%

756 Electric Crossing

Theme / Subtheme Trains / 4.5V / 12V
Year 1974
Pieces 5
Availability Retired
756 LEGO Trains Electric Crossing
Retail $9.99
Value $47.98
Growth  +380.3%
Annual growth 3.1%

My Collection

12 V Transformer Reviews

22 reviews
4.7
Collectors
Investors
BrickTrains-Sets
“The Lego 741 12v Transformer is the control for the new Lego 12 volt line. Much like the 742: 12v Transformer for 100V Mains, this one is for the normal power outlet. The 742 was made especially for electrical outputs that generate 100 volts of electricity. In the US the... More average voltage in an outlet is 110 – 120 volts.”
Full review at bricktrains-sets.com

About Trains 4.5V / 12V

In 1972 LEGO released the 4.5V and 12V train sets as part of the Blue Era which was named because of the rail color. These train sets used additional conductor rails mounted between the standard 4.5V rails and 12V motors contained in the same housings as the 4.5V motors, but with additional metal contacts attached to the bottom of the housings.

4.5V / 12V consists of 83 sets that ran from 1972 to 1986. As of today, 7750 Steam Engine with Tender is the most valuable 4.5V / 12V set with an estimated new/factory sealed value of $6,301.
Read more