26 x 30 Springs - With Threaded Bushings
Models with springs using threaded (TB-73) bushings; Very uncommon
Except where noted, 2-leaf springs have 2 1/4" eyes with reducing sleeves for the TB-73 bushings.
Refer to remarks for springs identical but using bronze (RNK) bushings.
RNK springs can replace TB-73 when necessary, as they share the same eye size.