with these large opening vials. •29435-U PK100, Certified 200 muL glass inserts, mandrel precision point, 6 X 29mm, with bottom spring •29436-U PK100, Certified 250 muL glass insert, conical bottom, 6 x 31 mm •29437-U PK100, Certified 300 muL glass inserts, conical bottom, 6 x 30 mm •29441-U