Quantity: one piece Product net weight: 210 grams. Supplied with 304 stainless steel mounting screws Extra thick 3mm solid SUS-304 stainless steel casting with extra thick 3mm SUS-304 stainless steel chain - Heavy duty - This is a version heavier than the standard door protection chain which offers more resistance in the event of a malfunction trying to force. your way into your property Intruder - Provides a useful deterrent and significant delay in the event a burglar attempts to enter your home. It is processed by a fully automatic precision CNC machine tool (numerically controlled by computer) to ensure the stability and durability of the product quality, and has excellent straight wire drawing finish - the appearance of the product is very beautiful. Quality product. Never rust, always keep stainless steel - a durable, premium product that will last a lifetime