Changes

|diagram = O.21|lot = 556osl556|wagtype = 10 ton 4-w 4 plank open wagon|capacity = 10 tons

41277 was built in 1890 at Swindon to Diagram O.21, old series Lot 556.<ref>Railway Heritage Register Wagon Survey[[Bibliography#Other References|Atkins, Beard & Tourret (2013)]] pp. 25-26.</ref> The grease axle boxes were replaced with 'OK' oil axle boxes in 1910 and the original single sided brakes were upgraded in 1928 to comply with Board of Trade regulations by having a second lever operating a single shoe added to the other side.<ref>http://www.gwr813.org/gwr813newsletter_B1.htm</ref><ref>A history of GWR goods wagons. A G Atkins, W Beard, D J Hyde, R Tourret. 1986. ISBN 0-7153-8725-1</ref>