1:16 

I'm Starting my Rc Model Tank build starting with the "Metal Sherman VVSS (Vertical Volute Spring Suspension/Suspension System) and Main Idler, Drive Sprocket Upgrade Assembly." + Short Review.
Here are the links to both the haya website which is the best for parts, where I bought the tank, and the metal upgrade set on eBay.
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Haya Ltd.
www.hayaltd.co...
---------------------------------------------------------------------------------------------------------------------------Heng Long 1/16 Sherman M4A3 RC Tank Radio Remote Controlled Tank Model with Metal Steel Gearbox/Seller/BigZ BoyZ
www.amazon.co....
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1/16 RC HengLong 3898 Metal Tracks Sprockets Idlers Wheels USA M4A3 Sherman Tank.
www.ebay.co.uk...
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Heng Long Tamiya Taigen 1/16 Tank 7.2V 2000 / 5000 mAh Ni-MH Battery & Charger.
www.ebay.co.uk...
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