Hi @highdesertdog! I'm really excited for you and your new mountain bike! Any of our mountain biking shoes for platform pedals would work well in giving you some more grip on the pedals while also being more durable than riding with regular sneakers.  Personally, I really like the Five Ten Freerider Mountain Bike Shoes.  These come in regular U.S. sizing so no conversion is necessary.  For other shoes, such as the Shimano GR5 or Pearl Izumi X-Alp Flow, if your running shoe size is 9.5 US, I recommend starting with an EU 43.  If you measure at 9.5, I would go up to EU44.

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