Extruded and CNC-machined from 6061-T6 aluminum, Box Two(TM) Stem Spacer Kits feature a lightweight design. Weights range from 0.24 to 0.29 ounces (6.7 to 8.2 grams), depending on the size. Sold in packs of five, each set provides spacing adjustments from 1 to 20 millimeters. FEATURES - Lightweight Design - Adjustment options from 1 to 20 millimeters - Fits 1" or 1-1/8" Steerer Tubes and Standard 22.2mm Handlebars SPECIFICATIONS - Inner () 1" or 1-1/8" - Height 1mm, 3mm, 5mm, 10mm 1mm, 3mm, 5mm, 10mm - Material 6061-T6 Aluminum 6061-T6 Aluminum - Weight 6.7 grams / 0.24 ounces 8.2 grams / 0.29 ounces