In the endoscopic treatment of superficial femoral artery and/or proximal popliteal artery in patients with lower extremity arteriosclerosis occlusion, the intercalation caused by the predilation of increasing caliber balloon and matching caliber balloon was compared, and then the impact of the two predilation methods on the intraoperative treatment strategy and short and medium-term prognosis was analyzed. The study was designed as a prospective, multi-center, single-blind, randomized, controlled study. It is planned to set up 5-10 research centers with 340 subjects, and the single center will be less than or equal to 100 subjects, in the form of competition from each research center.

Inclusion Criteria:

1. Target lesions from superficial femoral artery to popliteal artery P1 segment; Proximal anatomical markers of target lesions:

   1. 1cm below the fork of the common femoral artery;
   2. Distal anatomical sign of target lesions: upper border of patella;

2. Target lesions may be single, combined, or tandem primary lesions of stenosis and/or occlusion, and meet one of the following criteria:

   1. In contrast, The stenosis rate was greater than or equal to 70% and less than 100%, and the total length of the lesions was greater than or equal to 40mm and less than or equal to 200mm.
   2. The total length of the lesion is less than 100mm.
   3. The total length of the lesion is less than or equal to 200mm, and the length of the occlusion segment is less than or equal to 100mm.

   Note: the distance between the lesions is no more than 30mm, and the distance between the lesions is > 30mm. Patients with multiple target lesions judged as 2 or more independent lesions met the inclusion criteria.

3. The diameter of the reference vessels of target lesions shall be 4mm or more and 7mm or less.

4. If the subject has ipsilateral iliac or lower knee lesions to be treated, the above lesions shall be successfully treated with target lesions, and the following criteria shall be met:

   1. Residual stricture of the common iliac lesion < 30%;
   2. An upper knee has at least one or more free outflow tract, i.e., residual stenosis < 50%;
   3. No embolism, rupture or other serious adverse events occurred during the operation.

5. The pregnancy test results of fertile female subjects must be negative and there is no pregnancy plan during the study period;

6. The patient or client signs the patient's informed consent;

7. Understand and accept the duration of this study, and be able to cooperate with follow-up and evaluation;

8. Subject's life expectancy is greater than or equal to 12 months after evaluation by the investigator.

Exclusion Criteria:

1. The investigator believes that the subject has the possibility of non-compliance with the follow-up plan;

2. Patients with cerebral apoplexy or st-segment elevation myocardial infarction in the last 3 months;

3. Combined with the following diseases

   1. Patients diagnosed with thrombotic occlusive vasculitis;
   2. combined with abdominal aortic aneurysm/thoraco-abdominal aortic aneurysm (with mural thrombus inside the aneurysm cavity);
   3. coagulation defect;
   4. high coagulation status;

4. blood index

   1. Serum creatinine > 170umol;
   2. White blood cell count < 3.0 x 109/L or > 14.0 x 109/L;
   3. Patients with platelet count < 80 x 109/L or > 500 x 109/L;

5. Patients who are known to be allergic to anticoagulant, antiplatelet, contrast agent and other drugs; Examples: heparin, clopidogrel, iodixanol, etc.

6. Target lesions are non-primary lesions of restenosis and anastomotic stenosis within the stent;

7. Acute or subacute thrombosis of target lesions;

8. There are aneurysms in the vicinity of target lesions, and the proximity refers to no more than 20mm.

9. The patient is a lactating woman or a pregnant woman.