Shimano SM-SH51/56 Cleat adapter that enables the attachment of all 2 bolt SPD cleats onto a 5 hole road shoe - 360 Cycles
Amazon.com : CyclingDeal Bicycle Shoes Cleats Adapters - for MTB Shoes to Use with Cleats of Road Bike Pedals - Compatible with Shimano SPD-SL, Look KEO & Look Delta - Converting Adapters
Surprise! SPD adapters on road shoes are NOT awesome... #newshoeday - YouTube
3 bolt to 2 bolt SPD adapters. Convert your road cycling shoes to 2 bolt SPD - YouTube
Shimano SPD Cleat Stabilising Adapters | Evans Cycles
SHIMANO SPD CLEAT ADAPTER SM-SH41 FITS 3-5 HOLES TYPE SPD-SL SHOES | eBay