Another Toei 10-300 Series Train at Chitose-karasuyama No.4 Railroad Crossing 7

Car No.1 has number “10-519.” Car No.2’s number is “10-518.” Car No.N of 10-300 series train has number “10-xx(10-N).” I think there is some reason for adopting such a numbering system for 10-300 series. But I do not know it.

Done