Originally Posted by gingerpeachy

First timer here, been lurking for a bit doing some research on bikes recently. I picked up a vintage steel Bianchi frameset with stamped horizontal dropouts without a derailleur hanger. The serial number is stamped onto the frame under the headset: 3 35436. There is also a sticker on the downtube that says Tubi Calibrati 1-20, which leads me to believe it is Hi-Ten based off of previous forum posts here. The Bianchi logo is black, and the frame is celeste. There appear to be no bottle bosses on the downtube.

I'm assuming it is a 1973 low end Bianchi, perhaps a Rekord? Would love any insight into identifying this bike, TIA. I'm undertaking my first bike build so any info would be appreciated!