This is it. 7€, model no Z30817.
Big, rugged, both blades locking, seath with 10 spare double blades. Unknown steel (non inoxydable I presume).
It belongs to a hard worker's tool box. Good for wall to wall carpets.
Ἄφοβον ὁ θεός, ἀνύποπτον ὁ θάνατος· καὶ τ’ ἀγαθὸν μὲν εὔκτητον, τὸ δὲ δεινὸν εὐκαρτέρητον.
Φιλόδημος Γαδαρεύς