The objective of this clinical study is to evaluate the performance of the Optimized FLAIR™ Delivery System.

Inclusion Criteria:

• The subject is either a male or non-pregnant female ≥ 18 years old.
• The subject has been properly informed about the study per IRB requirements, and has signed and dated the IRB-approved ICF.
• The subject is willing to comply with the protocol requirements and can be contacted by telephone.
• The subject has a synthetic AV access graft located in an arm that has been implanted for > 30 days and has undergone at least one successful dialysis session prior to the index procedure.
• Angiographic evidence indicates that the subject has a stenosis of >50% located at the graft-vein anastomosis of the subject's synthetic AV access graft.
• The target lesion is estimated to be ≤ 7 cm in length by angiography prior to performance of any interventional procedures.
• The entire target lesion is located within 7 cm of the graft-vein anastomosis, as verified by angiography, such that approximately 1 cm of the FLAIR™ Endovascular Stent Graft will extend into non-diseased vein and approximately 1 cm but no more than 2 cm of the FLAIR™ Endovascular Stent Graft will extend into non-diseased AV graft.
• Graft diameter at the deployment site is between 5 mm and 8 mm, as verified by angiography.
• Full expansion of an appropriately sized angioplasty balloon, in the operator's judgment, can be achieved during primary angioplasty.

Exclusion Criteria:

• The subject has a life expectancy of < 6 months.
• The presence of a previously placed stent and/or stent graft located in the treatment area. The treatment area is defined as the entire target lesion and 1 cm of landing zone into both non-diseased AV graft and non-diseased vein.
• The subject has an infected AV access graft or other infection.
• The location of the target lesion would require that the FLAIR™ Endovascular Stent Graft be deployed fully across the elbow joint.
• The location of the target lesion would require that the FLAIR™ Endovascular Stent Graft cross an angle (between the outflow vein and synthetic AV access graft) that is > 90 degrees.
• The subject has an uncorrected blood coagulation disorder.
• The subject has a known allergy or sensitivity to contrast media which cannot be adequately pre-medicated.
• Subject is currently enrolled or scheduled to be enrolled in other investigations that conflict with follow-up testing or confounds data in this trial.
• The subject has a known hypersensitivity to nickel-titanium.

30 days post implantation