The invention relates to a closure piece , in particular a syringe closure piece for closing a distal opening (4) of a syringe cone of a syringe body , for example , in a sealed manner , wherein the closure piece , in particular the syringe closure piece , comprises a fastening element (3) which is or can be arranged on the syringe body about the distal opening , in particular on the syringe cone , and which is in particular a Luer lock or a Luer lock adapter (3.1), and a closure cap (20) which closes the distal opening , for example the syringe cone, in a sealed manner and which is connected releasably to the fastening element. The invention is characterized in that the closure cap , in the area of the fastening element , is connected by material bonding , preferably exclusively by material bonding , to the fastening element , in particular to the Luer lock or the Luer lock adapter ,by at least one connection point or one connection surface, and the closure cap comprises a hard area (30) and an elastomer part (10), wherein the elastomer part securely closes the distal opening in particular by simply being placed on or enclosing a short portion in the area of a tip of the distal opening.
