# `GSGlyph.bottomMetricsKey`

*Instance Property*

Glyph-level metrics key for the bottom side bearing.

## Declaration

```swift
var bottomMetricsKey: String? { get set }
```

```objc
@property (nonatomic, copy) NSString * bottomMetricsKey;
```

[See also `bottomMetricsKey` in the Python API](https://docu.glyphsapp.com/#GSGlyph.bottomMetricsKey)

```python
pyobjc_instanceMethods.bottomMetricsKey() -> str
pyobjc_instanceMethods.setBottomMetricsKey_(bottomMetricsKey: str)
```

## Discussion

A layer-specific metrics key overrides this value.

## See Also

### Metrics Keys

- [`GSGlyph.leftMetricsKey`](/Core/GlyphsCore/GSGlyph/leftMetricsKey) — Glyph-level metrics key for the left side bearing.
- [`GSGlyph.widthMetricsKey`](/Core/GlyphsCore/GSGlyph/widthMetricsKey) — Glyph-level metrics key for the advance width.
- [`GSGlyph.rightMetricsKey`](/Core/GlyphsCore/GSGlyph/rightMetricsKey) — Glyph-level metrics key for the right side bearing.
- [`GSGlyph.topMetricsKey`](/Core/GlyphsCore/GSGlyph/topMetricsKey) — Glyph-level metrics key for the top side bearing.
- [`GSGlyph.vertOriginMetricsKey`](/Core/GlyphsCore/GSGlyph/vertOriginMetricsKey) — Glyph-level metrics key for the vertical origin.
- [`GSGlyph.vertWidthMetricsKey`](/Core/GlyphsCore/GSGlyph/vertWidthMetricsKey) — Glyph-level metrics key for the vertical advance width.
- [`GSGlyph plainMetricsKey:`](/Core/GlyphsCore/GSGlyph/plainMetricsKey:) — The stored glyph-level metrics key for a metric side, or `nil` when none is set.
- [`GSGlyph setPlainMetricsKey:side:`](/Core/GlyphsCore/GSGlyph/setPlainMetricsKey:side:) — Sets the glyph-level metrics key for a metric side.
- [`GSGlyph validateMetricsKey:error:`](/Core/GlyphsCore/GSGlyph/validateMetricsKey:error:) — Validates the syntax of a proposed metrics key.