I have a 99K with out the stitch length lever and a turn knob in stead. I'm sure you know; the Spartan is identical to the later 99, the difference is no fancy decals, there's no mount for the bracket holding the Singer lamp. I thought it just came with out the lamp, but someone told me there is no screw hole for the bracket at all on them. I guess some have been a bit inventive and added light to their Spartan. The bobbin winder is manually press down; in other words, no click in place or auto release. The pedal is smaller; and I don't think it came with a case either, just a minimal base. The internal parts are identical, so a smooth running very capable little straight stitcher. Some love them for their minimal base, but I lean towards my 99K, I like the gold decals, lamp and bent wood case. I think you have the original base. I don't know all the variations on this model, but the white plastic bases some come in are later replacements. There's something to the minimal stripped down look though.