I have acquired several large bags of LEGO - most are the tradition bricks, but what kit are these (see photo) rail-type pieces from? They are identified on the reverse with a letter, such as "E", and a 1 or 2-digit number. Some of the rails contain small teeth the entire length - some are smooth.
2Related: What different types of train tracks exist– UliSep 27, 2020 at 18:50
That gear doesn't look like Lego at all. But those rails where the normal rails in the 70's– TonnySep 29, 2020 at 14:32
@Tonny , The gear is part # 743 :Technic, Gear Samsonite 35 Tooth– SyberionOct 2, 2020 at 21:51
@Syberion Interresting... The early Technic gears I'm familiar with are from the 70's. The red (small) , blue (medium) and yellow (big) ones with the white axles. Seems these are even bigger. I had never seen them before.– TonnyOct 3, 2020 at 11:57
The rails with the "small teeth" are
Part No: 3230a , Train, Track Tapered Rail Curved Inside
Part No: 3229a Name: Train, Track Tapered Rail Curved Outside