# Pololu Micro Gripper Kit (position feedback)

> Pololu 3551 micro gripper kit: rack-and-pinion parallel paddles with a 32 mm range, driven by the included FEETECH FS90-FB micro servo whose extra wire reports position (0.5 V open to 2.2 V closed); 4.8–6 V, ~800 mA stall at 6 V; 62.3 × 48.3 × 23 mm, 30 g, POM — the gripper of Pololu's Romi robot arm.

- Manufacturer: Pololu
- Part number: 3551
- Category: Grippers & end effectors
- Canonical page: https://www.xirkit.io/products/pololu-micro-gripper-kit-position-feedback-886f
- Structured JSON: https://www.xirkit.io/products/pololu-micro-gripper-kit-position-feedback-886f/data.json
- Source: Xirkit structured parts catalog — every value traced to a cited document; unknowns are explicit.

## Key specifications

| Property | Value |
| --- | --- |
| Effector type | parallel gripper |
| Degrees of freedom | 1 |
| Max jaw opening | 32 mm |
| Drive | servo |
| Actuator | FEETECH FS90-FB micro servo with position feedback |
| Control | PWM (+ analog position feedback) |
| Mount pattern | 2 × Ø2.4 mm holes for #2 screws; 2 × Ø4.2 mm holes |
| Weight | 30 g |
| Supply voltage | 4.8–6 V |
| Dimensions | 62.3 × 48.3 × 23 mm |

## Where to buy

| Supplier | Price | Stock | Checked | URL |
| --- | --- | --- | --- | --- |
| www.pololu.com | 29.95 USD | in_stock | 2026-09-29 | https://www.pololu.com/product/3551 |

## FAQ

**What voltage powers the Pololu Micro Gripper Kit?**

Supply range 4.8–6 V.

**How much does the Pololu Micro Gripper Kit cost?**

From $29.95 at www.pololu.com. Prices are observed unit prices before tax and shipping.

**What are the Pololu Micro Gripper Kit dimensions?**

62.3 × 48.3 × 23 mm. A STEP model is available for enclosure fit checks.

**Where does this Pololu Micro Gripper Kit data come from?**

Every value in this record is traced to a source — 2 documents including the board and chip datasheets — with the page and table cited per value. Unknowns are left explicit, never guessed.

## Sources

- [Pololu Micro Gripper Kit (position feedback) datasheet](https://www.pololu.com/product/3551)
- [www.pololu.com listing](https://www.pololu.com/product/3551)

## Part graph

### Alternatives (by use case)

- [goBILDA Rotating-Jaw Gripper Kit (servo-driven)](https://www.xirkit.io/products/servocity-gobilda-rotating-jaw-gripper-kit-servo-driven-8f11) — Both serve grasping and manipulation — check the trade-offs; $29.95 vs $29.99
- [goBILDA Parallel Gripper Kit (servo-driven)](https://www.xirkit.io/products/servocity-gobilda-parallel-gripper-kit-servo-driven-09c2) — Both serve grasping and manipulation — check the trade-offs; $29.95 vs $34.99