The back contains 7 scales of the following types:
| Type (click to view scale details) |
Range & Units | Numbered | Geometry | Location |
|---|---|---|---|---|
| Altitude | 0 - 90, Degrees of arc | Every 5 degrees | Circular, concentric | Upper right quadrant of outer circular on back of instrument. |
| Altitude | 0 - 90, Degrees of arc | Every 5 degrees | Circular, concentric | Upper left quadrant of outer circular on back of instrument. |
| Declination | Zodiacal sign | Not numbered | Arc | Upper right quadrant (inside circular scales) |
| Sine/Cosine | 1/60 of quadrant radius | Not numbered | Angle | Upper left quadrant (inside circular scales) |
| Cotangent | 0 - 45, Fingers | Every 5 fingers | Circular, concentric | Lower left quadrant of outer circular on back of instrument. |
| Cotangent | 0 - 30, Feet | Every 5 feet | Circular, concentric | Lower right quadrant of outer circular on back of instrument. |
| Shadow square | 0 - 8, Feet | Every 2 feet | Box | Left hand vertical 'face' of the shadow square (in LL) |
| Shadow square | 0 - 8, Feet | Every 2 feet | Box | Left hand bottom face of the shadow square (in LL) |
| Shadow square | 0 - 12, Feet | Every 2 feet | Box | Right hand bottom face of the shadow square (in LR) |
| Shadow square | 0 - 12, Feet | Every 2 feet | Box | Right hand vertical face of the shadow square (in LR) |
| Transcription | Translation | Notes | Type |
|---|---|---|---|
| هذه الأصطرلاب العبد الفقير ٳلى الله الغفار في سنة ست وثمانين وثمان مائة شمس الدين محمد صفار | This astrolabe (was made by) the servant, yearning for God the much-forgiving, Shams ad-Dīn Muḥammad Ṣaffār, in the year 886. | Inscription in the lower half | Maker's signature |
| ظل الأصابع عمد ظل الأقدام مديد | The shadow of the fingers is vertical / The shadow of the feet is extended. | Upside down within the shadow square | Scale label |