Both Shunting Tank Engines with 10 members each built, with 2 batches of 5. Each batch looking very different to accomidate for improving fuel capacities.
Examples are shown here
Not to mention similar numbering too! First member ending in 00, and the last member ending in 09.
Need help finding a plarail piece! It was this modern station piece you’d use with these switches, a clear see through top, and had a dark blue base, similar to Tomy Trains. If it came with a set, the name of the set would be appreciated too!!