Roller shutter door motor AC 230V or ... twisted off. TOMA limit: non-mandrel structure, high strength, wear-resistant, easy hand operation.2. ... limit screw rod: composes of brass, featuring high accuracy, resistant to wear, antirust, stable limit ... quality alloy steel, therefore the products are high abrasive and with long life. The loading capacity has also been increased by 40%. Roller shutter door ...