A4. 10x1 male spigot left
1. A4 10×1-left red 01z2351035 $22.0
←reserve on↓ off→,made in Italy by OMG
2. A4b 10×1 spigot left 403200 $26
←reserve on↓ off→, made in Taiwan by FS
Links to photos of examples:
1977 Motobecane frame A4b replacement
1978 Gitane Sport original
1978 Motobecane frame replacement
1978 Motron Classic A4b replacement
1976 Bianchi Snark original
Any top-tank model, with a 10 x 1 threaded hole on the right side (and nothing nearby) would use this A4 petcock.
Motobecane: This spigot-left valve fits 1970’s sheet-metal-frame Motobecanes, where there is a tight space. It substitutes for the spigot-back original configuration. The fuel hose is routed slightly better than it was with the original valve. See above valve A3.
Cutting the Motobecane side cover to fit an OMG petcock