diff --git a/frc971/zeroing/zeroing.h b/frc971/zeroing/zeroing.h
index e969a88..e0c6169 100644
--- a/frc971/zeroing/zeroing.h
+++ b/frc971/zeroing/zeroing.h
@@ -421,6 +421,74 @@
   double position_;
 };
 
+// Estimates the position with an absolute encoder which also reports
+// incremental counts.  The absolute encoder can't spin more than one
+// revolution.
+class AbsoluteEncoderZeroingEstimator
+    : public ZeroingEstimator<AbsolutePosition,
+                              constants::AbsoluteEncoderZeroingConstants,
+                              AbsoluteEncoderEstimatorState> {
+ public:
+  explicit AbsoluteEncoderZeroingEstimator(
+      const constants::AbsoluteEncoderZeroingConstants &constants);
+
+  // Resets the internal logic so it needs to be re-zeroed.
+  void Reset() override;
+
+  // Updates the sensor values for the zeroing logic.
+  void UpdateEstimate(const AbsolutePosition &info) override;
+
+  void TriggerError() override { error_ = true; }
+
+  bool zeroed() const override { return zeroed_; }
+
+  double offset() const override { return offset_; }
+
+  bool error() const override { return error_; }
+
+  // Returns true if the sample buffer is full.
+  bool offset_ready() const override {
+    return relative_to_absolute_offset_samples_.size() ==
+           constants_.average_filter_size;
+  }
+
+  // Returns information about our current state.
+  State GetEstimatorState() const override;
+
+ private:
+  // The zeroing constants used to describe the configuration of the system.
+  const constants::AbsoluteEncoderZeroingConstants constants_;
+
+  // True if the mechanism is zeroed.
+  bool zeroed_;
+  // Marker to track whether an error has occurred.
+  bool error_;
+  // The first valid offset we recorded. This is only set after zeroed_ first
+  // changes to true.
+  double first_offset_;
+
+  // The filtered absolute encoder.  This is used in the status for calibration.
+  double filtered_absolute_encoder_ = 0.0;
+
+  // Samples of the offset needed to line the relative encoder up with the
+  // absolute encoder.
+  ::std::vector<double> relative_to_absolute_offset_samples_;
+
+  MoveDetector<AbsolutePosition> move_detector_;
+
+  // Estimated start position of the mechanism
+  double offset_ = 0;
+  // The next position in 'relative_to_absolute_offset_samples_' and
+  // 'encoder_samples_' to be used to store the next sample.
+  int samples_idx_ = 0;
+
+  // Number of NANs we've seen in a row.
+  size_t nan_samples_ = 0;
+
+  // The filtered position.
+  double position_ = 0.0;
+};
+
 }  // namespace zeroing
 }  // namespace frc971