diff --git a/lib/www/server/lib/binary/bundle.js b/lib/www/server/lib/binary/bundle.js
index 3ba8f2c..1f161b6 100644
--- a/lib/www/server/lib/binary/bundle.js
+++ b/lib/www/server/lib/binary/bundle.js
@@ -38,7 +38,7 @@ function bundle (json, opts = {}) {
 
 		return encode.sequential(json, el => el.sailline, el => el.point, deltas, values, type)
 
-	} if (type == 1) {
+	} else if (type == 1) {
 		/* Preplot information – source line points
 		 *
 		 * elem 0: Float32Array Longitude
@@ -273,6 +273,88 @@ function bundle (json, opts = {}) {
 		});
 
 		return encode.sequential(json, el => el.sequence, el => el.point, deltas, values, type)
+	} else if (type == 0xa) {
+		/* 4D comparison data:
+		 *
+		 * elem0: i differences
+		 * elem1: j differences
+		 *
+		 * Note that line/point may not be unique.
+		 *
+		 */
+
+		/*
+		deltas.push({
+			key: el => el.baseTStamp,
+			baseType: BigUint64Array,
+			incrType: Int32Array
+		});
+
+		deltas.push({
+			key: el => el.monTStamp,
+			baseType: BigUint64Array,
+			incrType: Int32Array
+		})
+		*/
+
+		values.push({
+			key: el => el[2],
+			type: Float32Array
+		});
+
+		values.push({
+			key: el => el[3],
+			type: Float32Array
+		});
+
+		/*
+		values.push({
+			key: el => el.baseSeq,
+			type: Uint16Array
+		});
+
+		values.push({
+			key: el => el.monSeq,
+			type: Uint16Array
+		});
+		*/
+
+		return encode.sequential(json, el => el[0], el => el[1], deltas, values, type)
+	} else if (type == 0xc) {
+		/* 4D comparison data (reduced sample)
+		 *
+		 * Input is comparison records, i.e.:
+		 * [ [ line, point, δi, δj ], … ]
+		 *
+		 * elem0: line
+		 * elem1: point
+		 * elem2: δi
+		 * elem3: δj
+		 *
+		 * Note that the chunk's `i` and `j` values are not used
+		 */
+
+		values.push({
+			key: el => el[0],
+			type: Uint16Array
+		});
+
+		values.push({
+			key: el => el[1],
+			type: Uint16Array
+		});
+
+		values.push({
+			key: el => el[2],
+			type: Float32Array
+		});
+
+		values.push({
+			key: el => el[3],
+			type: Float32Array
+		});
+
+		return encode.sequential(json, el => 0, el => 0, deltas, values, type)
 	}
 }