Originally Posted by
FBinNY
I suspect that this is a Chinese freewheel and is removed the same way as any other freewheel. The remover is hexagonal and requires that either the axle or the lockout is removed first to allow access.
If I remember correctly, the hex is not the same as any standard bolt head, so you'll have to get busy with a file.
Hmm, "Shimano" is clearly visible, so it's either a version of Uniglide cassette or a Shimano freewheel. If there's no DS locknut it's a cassette.