Wheels Manufacturing Bb30-Out-Spac 42Mm Id Al Bb Spacer Kit Black 3/Bg 1 x 2.5mm, 2 x 1.0mm, 42mm ID, black anodized aluminum Use for adjusting chainline or eliminating bearing play in cranks with BB30 outboard bottom brackets Bottom bracket cup and spindle spacers for adjusting chainline or bearing play.