They are ideal for replacing the plastic Peco/ Farish/ wheels on early wagons. The back to back of the rims is 7 mm. Check out the pictures.
N Gauge Wheels Ect
N Gauge Wheels Chassis Parts
Dapol 113076 JNA N Gauge Wheels Bogie (Pk1)
PECO ACCESSORIES NR-101 SPOKED WHEELS ON AXLES (8 WHEELS) - N GAUGE
P&D Marsh N Gauge N Scale B157 Cart wheels (20) castings require painting
12pcs Model Train N Gauge 1:150 POM Bogies with Couplers 36" Plastic Wheels