Shell

No insulation

Warm

1–79 g/m²

Warmer

80–119 g/m²

Warmest

120+ g/m²

The Drop's insulation-weight guide, not an industry-wide warmth standard. g/m² describes insulation weight per square metre, not a temperature rating. Insulation type, coverage, layers and activity all affect warmth. These ranges are intended for synthetic insulation, not down fill power.

Waterproof ratings measure how much water pressure a fabric withstands before water penetrates in a hydrostatic-head test. 20K means a 20,000 mm water column under the stated test conditions. Higher numbers indicate greater pressure resistance when tested the same way. Seams, zippers, garment design and fabric condition also affect protection.

GORE-TEX® identifies a fabric technology, not a numerical rating above 30K. It is shown separately because its waterproofing and breathability depend on the specific product technology.

Numerical breathability ratings commonly use moisture vapour transmission rate (MVTR): grams of water vapour passing through one square metre of fabric in 24 hours. 20K means 20,000 g/m²/24 h. Higher values indicate more vapour transfer within the same test method; different methods are not directly comparable. RET is a different measure, where lower values indicate better breathability, and is not plotted on this scale.

GORE-TEX® identifies a fabric technology, not a numerical rating above 30K. It is shown separately because its waterproofing and breathability depend on the specific product technology.