This steel long side rail mount can be clamped on Accumount steel Swiss K31 clamp-on mount. The size of the rings is 26.5mm in diameter, but it comes with 4 steel 1 inch inserts so that you can put 1 inch scope on it.
LSR mount and a ZF 39 scope
Long side rail mount on Swiss K31
Long side rail mount on Swiss k31
Long side rail mount on Swiss K31
Long side rail mount on German K98
Long side rail mount on Yugo M48