Spring Loaded Adjustable Height: 3 inches (75mm) heavy-duty doorstop with built-in spring for seamless height adjustment, fits clearances 0.8-3 inches (not for <0.4 inches). Custom-tailors to your door’s unique gap for a secure hold every time Dual Anti-Slip Rubber Lock Design: Top & bottom anti-slip rubber pads and spring-driven tension lock the door firmly open—no slipping, shifting or moving, even against gusts of wind. Secures tightly between floor and door, preventing unexpected closure Universal Multi-Surface Compatibility: Ultra-strong grip on wood, cement, carpet, marble and tiles. Ideal for heavy commercial, metal, double, safety, glass and balcony doors, reliable hold for all heavy & light doors Waterproof & Rustproof Build: Crafted from premium stainless steel core and durable rubber. Stands up to daily wear, moisture and heavy use. Ideal for home, commercial and public areas Effortless Use & Remove: No bending or fumbling—one-step use & removal. Step on the raised side to compress the spring, adjust height to clamp and lock the door open; step again to release and remove the doorstop in seconds Elevate door security and convenience with our 3-inch (75mm) heavy-duty spring loaded door stop! Built-in spring enables seamless height adjustment for 0.8-3 inch door clearances (not for <0.4 inches), custom-fitting your door for a secure hold. Dual top and bottom anti-slip rubber pads, spring-driven tension lock doors firmly open—no slipping, even against gusts of wind, preventing unexpected closure. Ultra-strong grip works on wood, cement, carpet, marble, tiles; ideal for commercial, metal, double, glass, balcony doors (all heavy & light types). Crafted from premium stainless steel core and durable rubber, waterproof and rustproof for long-lasting use at home, commercial & public areas. Effortless one-step operation: step on the raised side to compress/adjust/lock, step again to release—no bending or fumbling, quick & easy for all settings!