The test tube brushes are made of iron frame with nylon or pig hair as the brush Totally we have 3 sizes for choice:
Large size:full length:260mm; Brush length:128mm; brush diameter:17 mm
Medium size:full length:235mm; Brush length:118mm; Brush diameter:25 mm
Small size:full length:185mm; Brush length:88mm; Brush diameter:33 mm
Customized size available