Iris scissors are a type of small, sharp scissors commonly used in ophthalmology, surgery, and other delicate procedures . A 4.25 inch iris scissor is a specific size within the range of commonly available iris scissors.
 
The size refers to the total length of the scissors, including the handles and blades. Iris scissors typically come in straight or curved blade varieties. Straight blade iris scissors are better suited for clipping sutures or bandages, while curved blade iris scissors are better suited for dissection or cutting around curves.
 
Here are some additional details about iris scissors:
Typically made from high-quality stainless steel for durability and sharpness
May have blunt or sharp tips, depending on the intended use
The handles may have ring or spring action styles
Reusable, but require proper sterilization between uses