YihuaTop Boot Stretchers

Here’s a product-style description for a Boot Stretcher for Cowboy Boots that matches what you described — adjustable width, suitable for wide feet, and typically available in yellow (medium size):

Boot Stretchers for Cowboy Boots – Adjustable Width Shoe Trees for Wide Feet (Yellow, M)

👢 Designed for Wide Feet & Cowboy Boots
Adjustable boot stretcher made to expand tight cowboy boots and other types of footwear, helping relieve pressure and improve comfort — particularly for men and women with thick, wide feet. These stretchers work best on leather and softer materials by widening the boot’s width and instep. (Ubuy Pakistan)

🔧 Adjustable & Easy to Use
Simply insert the stretcher into your boot, push it forward, and turn the handle clockwise to gradually widen the boot’s interior. For best results, leave it in place for 24–48 hours and consider using a leather stretch spray to help soften the material. (walmart.com)

📏 Medium Size (M) Fit
The medium version generally fits men’s US sizes around 7.5–11.5 and many women’s sizes, making it a versatile choice for everyday cowboy boots and other shoes. (Guys And Dolls Shoe Care)

🛠️ Durable Construction
Made from sturdy ABS plastic and metal parts that withstand the pressure needed to stretch footwear without damaging the boot’s interior. The metal handle and screw mechanism provide reliable long-term use. (Ubuy Pakistan)

🎯 Targeted Stretching
These stretchers can expand the width of the toe box and instep, helping alleviate tight spots, pressure points, and discomfort associated with narrow boots. (bestproductsreviews.com)

If you’d like, I can also suggest specific listings from Amazon or other stores that match exactly this description and include price comparisons.