Those cleats and pontoons were designed for the original Shimano road SPD pedals. Two versions of the cleats were made and per my understanding one version is definitely not compatible with current SPD pedals. The pedals those cleats were made for were manufactured ca 1996.
I suspect that the pontons could be made to fit modern SPD cleats with some grinding on the current design cleats but not with stock current cleats.
The plastic on the pontoons wears fairly rapidly if you walk much and is still on the slippery side as it is a relatively hard plastic, not ruber.
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Gear Hubs Owned: Rohloff disc brake, SRAM iM9 disc brake, SRAM P5 freewheel, Sachs Torpedo 3 speed freewheel, NuVinci CVT, Shimano Alfine SG S-501, Sturmey Archer S5-2 Alloy. Other: 83 Colnago Super Record, Univega Via De Oro
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