Part 21
| 21.mm Cast brass, four holes, feather key slot, U-shaped groove | 21.mm1 Cast brass, six holes, feather and tongue key slot | 21.mm1a) Cast brass, six holes, tongue key slot | 21.mm2) Milled brass, five large holes, tongue key slot |
21.mm2a) Milled brass, five smaller holes, tongue key slot | 21.mm2b) Milled brass, four large holes, tongue key slot | 21.mm2c) Milled brass, four large and four small holes, solid face, tongue key slot | 21.mm3) Brass two-part pressed wheel, 'Meccano patent' boss, 4 holes, tongue key slot |
21.mm4) Brass, '1911 patent' boss, 4 holes, tongue key slot | 21.br1b) Brass, '1911 patent' boss single tapped, 6 holes | 21.br1 Brass, 2 holes, standard boss single-tapped | 21.br2) Brass, as above but 4 holes, V-shaped groove from now on |
21.ni) Nickel plated steel discs, 4 holes | 21.ni1) Nickel plated steel discs, 6 holes | 21.br2a) Brass with 6 holes, as above | 21.br2b Brass, four standard holes, four small holes |
21.br3) Brass, eight standard holes, single tapped | 21.br3b, single tapped.',300,264,'white')) Brass, eight standard holes (four further out), single tapped | 21.br4) Brass, eight standard holes, as above but double tapped | 21.br5) Brass, eight standard holes, two sides symmetrical |
21.zn) Zinc plated, otherwise as above with steel faces | 21.nb) Blue, otherwise as above with steel faces | 21.re) Red, otherwise as above | 21.br) Brass, post-war stamping |
21.bs) Blackened steel 'economy' version of above † | 21.mb) Matt brass finished | 21.ye) Yellow | 21.db) Dark blue |
21.dy) Dark yellow | 21.ir) Iridescent |
