I have found the following for the hook and loop springs:
Bachmann springs are thinner than either LGB or USA and tend to break faster than the others.
Train-Li an advertiser in Garden Railways stocks the LGB coupler springs in packs of 8.
I am sure there are others that have them also and the LGB/USA/Bachmann hook and loops all take the same shape plastic springs
the little springs just where to you get these springs
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