diff --git a/daqbuffer/src/test.rs b/daqbuffer/src/test.rs
index 2a6444b..c34f433 100644
--- a/daqbuffer/src/test.rs
+++ b/daqbuffer/src/test.rs
@@ -1,7 +1,7 @@
 use crate::spawn_test_hosts;
 use bytes::BytesMut;
 use chrono::{DateTime, Utc};
-use disk::agg::streams::{Bins, StatsItem, StreamItem};
+use disk::agg::streams::{StatsItem, StreamItem};
 use disk::binned::query::{BinnedQuery, CacheUsage};
 use disk::binned::{MinMaxAvgBins, RangeCompletableItem, WithLen};
 use disk::frame::inmem::InMemoryFrameAsyncReadStream;
diff --git a/disk/src/agg/scalarbinbatch.rs b/disk/src/agg/scalarbinbatch.rs
index 1b79a8d..90fb472 100644
--- a/disk/src/agg/scalarbinbatch.rs
+++ b/disk/src/agg/scalarbinbatch.rs
@@ -1,5 +1,5 @@
 use crate::agg::binnedt::{AggregatableTdim, AggregatorTdim};
-use crate::agg::streams::{Appendable, Bins, StreamItem, ToJsonBytes};
+use crate::agg::streams::{Appendable, StreamItem, ToJsonBytes};
 use crate::agg::{AggregatableXdim1Bin, Fits, FitsInside};
 use crate::binned::{MakeBytesFrame, RangeCompletableItem, StreamKind};
 use crate::frame::makeframe::make_frame;
@@ -207,12 +207,6 @@ where
     }
 }
 
-impl Bins for MinMaxAvgScalarBinBatch {
-    fn bin_count(&self) -> u32 {
-        self.ts1s.len() as u32
-    }
-}
-
 pub struct MinMaxAvgScalarBinBatchAggregator {
     ts1: u64,
     ts2: u64,
diff --git a/disk/src/agg/streams.rs b/disk/src/agg/streams.rs
index 537db04..8be6214 100644
--- a/disk/src/agg/streams.rs
+++ b/disk/src/agg/streams.rs
@@ -17,11 +17,6 @@ pub enum StreamItem<T> {
     Stats(StatsItem),
 }
 
-// TODO remove in favor of WithLen:
-pub trait Bins {
-    fn bin_count(&self) -> u32;
-}
-
 pub trait Collector {
     type Input: Collectable;
     type Output: Serialize;