Road Bike Pedals Adapter Self-locking Clips for SPD KEO Bicycle Lock Pedal Converter for Shimano SPD LOOK KEO Bike Flat Pedal - AliExpress
Review: Every cyclist should have Pocket Pedals' slip-on platform pedals - Bikerumor
For Shimano | SPD and SPD-SL – Pocket Pedals
Crankwork can make your SPDs into flats with its adaptors
Amazon.com : Thinvik Clipless Pedal Adapter for Shimano SPD Pedal - Clip Pedal Convert to Universal Platform Pedal - (Only Work on MTB Bike Pedal : Sports & Outdoors
Amazon.com : Thinvik Bike Clipless Pedal Platform Adapters Compatible with Shimano SPD-SL/SPD,Look Keo/Delta,Peloton Bike Pedals and Cleats,Clipless Pedals Convert to Flat Pedals - CNC Aluminum Alloy : Sports & Outdoors
SPD Cleat Flat Pedal Adapters with Reflector PD22 Self Locking Flat Plate Conversion for M520 M540 M780 M515