Iwata Spring Guide A-SB I1701Iwata Spring Guide A SB I1701 An airbrush is only a true Iwata when it contains genuine Iwata parts. To keep your airbrush operating at peak performance, make sure the model number on the side of your airbrush is listed below. FOR USE WITH: Original, old style HP A HP B HP SB only. Iwata parts are precision crafted on the industry's most sophisticated machinery using the finest materials for consistent quality and performance. Every batch, every time.