Seat belts were unheard of.
Seat belts in 1965 were a mere formality, if found at all.
We had a 1965 Chevy station wagon. We didn’t think it had seat belts, but they had just fallen between the seat cushion and seat back. No one cared.
Seat belts were unheard of.
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I read recnetly that seatbelts were a low-cost option on some brand of 1960 American car. Only 5% of their customers ordered them. I think our ‘65 Bonneville had them. (Didn’t have auto-rollers or shoulder-belts.)