Strange metal part on real axle '86 schwinn

[SkyFlake]

I bought an old bicycle and see an unusual metal part attached on rear axle. Derailleur side. Starting from end I see a closed (no hole) bolt, two washers, then this "handle", a washer, then a deep nut, then a washer, then the derailleur, and then the bike frame. "Handle" is about one inch across and three inches deep, quite thick metal...flat but one edge has a perpendicular flange about 3/8 inch. No marks on handle. I think bike is a 1986 Schwinn Sprint made by Giant, with 24" wheels made in Taiwan by Femco (tire size a problem). I have a digital photo but it would not paste here. What is the function of this "handle"? Thanks.

[SkyFlake]

I think it may be a protector for the derailleur, rather massive and menacing. I think the bicycle is meant for children and I can't think of any other reason why this piece would be there than to protect the derailleur from getting smashed when a kid rides in to something and scrapes it. I will remove it. The tires...I have a request in at Harris Cyclery to see if they sell any tires to fit the strange rims.