LEGO Set

Mechanical Engineering Set

9665-1

Released: 2001 · Parts: 322 · Theme: Educational and Dacta

Mechanical Engineering Set (9665-1) is a Educational and Dacta LEGO set released in 2001 with 322 pieces. Browse the parts list, minifigures, and verify loose bricks with our free scanner. Collectors browsing Educational and Dacta sets use this inventory to verify loose parts, compare color variants, and read official build manuals without downloading PDFs. This set includes 84 unique part types.

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Buying checklist

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Release year

2001 (25 years ago — may be retired)
Catalog scale

322 parts listed · 84 inventory lines tracked
Minifigures

No minifigs in inventory (brick-only or Technic set)
Build manual

No digital manual in our catalog — check the box tab or LEGO.com
Gray era

Pre-2004 set — may use old light/dark gray instead of bluish gray
Shipping weight (est.)

~648 g for parts inventory (excludes box/minifig packaging)
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Market value

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