diff --git a/docs/api.md b/docs/api.md
index 5a24f16..4eb6a14 100644
--- a/docs/api.md
+++ b/docs/api.md
@@ -37,8 +37,8 @@ Call imported successfully
         {
           errorCount: number;
           freq: number; // in hertz
-          len: number; // in seconds
-          pos: number; // in seconds
+          len: number;  // in seconds
+          pos: number;  // in seconds
           spikeCount: number;
         }[];
 
@@ -49,7 +49,8 @@ Call imported successfully
 
         {
           pos: number; // in seconds
-          src: number; // the unit ID
+          src: number; // unit ID
+          tag: number; // [optional] unit tag
         }[];
 
 - **system** - [optional] system ID.
diff --git a/server/admin.go b/server/admin.go
index 6f6eb44..40472b1 100644
--- a/server/admin.go
+++ b/server/admin.go
@@ -271,8 +271,6 @@ func (admin *Admin) GetAuthorization(r *http.Request) string {
 }
 
 func (admin *Admin) GetConfig() map[string]interface{} {
-	// _, docker := os.LookupEnv("DOCKER")
-
 	systems := []map[string]interface{}{}
 	for _, system := range *admin.Controller.Systems {
 		systems = append(systems, map[string]interface{}{
@@ -284,14 +282,14 @@ func (admin *Admin) GetConfig() map[string]interface{} {
 			"led":          system.Led,
 			"order":        system.Order,
 			"talkgroups":   system.Talkgroups,
+			"units":        system.Units,
 		})
 	}
 
 	return map[string]interface{}{
-		"access":   *admin.Controller.Accesses,
-		"apiKeys":  *admin.Controller.Apikeys,
-		"dirWatch": *admin.Controller.Dirwatches,
-		// "docker":      docker,
+		"access":      *admin.Controller.Accesses,
+		"apiKeys":     *admin.Controller.Apikeys,
+		"dirWatch":    *admin.Controller.Dirwatches,
 		"downstreams": *admin.Controller.Downstreams,
 		"groups":      *admin.Controller.Groups,
 		"options":     *admin.Controller.Options,
diff --git a/server/api.go b/server/api.go
index d1b2c91..7d5f340 100644
--- a/server/api.go
+++ b/server/api.go
@@ -68,6 +68,7 @@ func (api *Api) CallUploadHandler(w http.ResponseWriter, r *http.Request) {
 			talkgroupGroup interface{}
 			talkgroupLabel interface{}
 			talkgroupTag   interface{}
+			units          interface{}
 		)
 
 		mediaType, params, err := mime.ParseMediaType(r.Header.Get("Content-Type"))
@@ -190,9 +191,22 @@ func (api *Api) CallUploadHandler(w http.ResponseWriter, r *http.Request) {
 									src["pos"] = uint(v)
 								}
 
-								switch v := v["src"].(type) {
+								switch s := v["src"].(type) {
 								case float64:
-									src["src"] = uint(v)
+									src["src"] = uint(s)
+
+									switch t := v["tag"].(type) {
+									case string:
+										var u Units
+										switch v := units.(type) {
+										case Units:
+											u = v
+										default:
+											u = Units{}
+										}
+										u.Add(uint(s), t)
+										units = u
+									}
 								}
 							}
 
@@ -246,6 +260,7 @@ func (api *Api) CallUploadHandler(w http.ResponseWriter, r *http.Request) {
 			talkgroupGroup: talkgroupGroup,
 			talkgroupLabel: talkgroupLabel,
 			talkgroupTag:   talkgroupTag,
+			units:          units,
 		}
 
 		if call.IsValid() {
diff --git a/server/call.go b/server/call.go
index e182ac1..926d0a8 100644
--- a/server/call.go
+++ b/server/call.go
@@ -39,6 +39,7 @@ type Call struct {
 	talkgroupGroup interface{}
 	talkgroupLabel interface{}
 	talkgroupTag   interface{}
+	units          interface{}
 }
 
 func (call *Call) IsValid() bool {
diff --git a/server/controller.go b/server/controller.go
index 87791da..f24b64d 100644
--- a/server/controller.go
+++ b/server/controller.go
@@ -288,6 +288,14 @@ func (controller *Controller) IngestCall(call *Call) {
 		system.Talkgroups = append(system.Talkgroups, talkgroup)
 	}
 
+	if controller.Options.AutoPopulate || system.AutoPopulate {
+		switch v := call.units.(type) {
+		case Units:
+			populated = true
+			system.Units.Merge(&v)
+		}
+	}
+
 	if populated {
 		if err = controller.Systems.Write(controller.Database); err != nil {
 			logError(err)
diff --git a/server/parsers.go b/server/parsers.go
index a4cd8f9..4815fec 100644
--- a/server/parsers.go
+++ b/server/parsers.go
@@ -109,22 +109,27 @@ func ParseTrunkRecorderMeta(call *Call, b []byte) error {
 				case float64:
 					freq["errorCount"] = uint(v)
 				}
+
 				switch v := v["freq"].(type) {
 				case float64:
 					freq["freq"] = uint(v)
 				}
+
 				switch v := v["len"].(type) {
 				case float64:
 					freq["len"] = uint(v)
 				}
+
 				switch v := v["pos"].(type) {
 				case float64:
 					freq["pos"] = uint(v)
 				}
+
 				switch v := v["spike_count"].(type) {
 				case float64:
 					freq["spikeCount"] = uint(v)
 				}
+
 				freqs = append(freqs, freq)
 			}
 		}
@@ -142,10 +147,25 @@ func ParseTrunkRecorderMeta(call *Call, b []byte) error {
 				case float64:
 					source["pos"] = uint(v)
 				}
-				switch v := v["src"].(type) {
+
+				switch s := v["src"].(type) {
 				case float64:
-					source["src"] = uint(v)
+					source["src"] = uint(s)
+
+					switch t := v["tag"].(type) {
+					case string:
+						var units Units
+						switch v := call.units.(type) {
+						case Units:
+							units = v
+						default:
+							units = Units{}
+						}
+						units.Add(uint(s), t)
+						call.units = units
+					}
 				}
+
 				sources = append(sources, source)
 			}
 		}
@@ -167,5 +187,11 @@ func ParseTrunkRecorderMeta(call *Call, b []byte) error {
 		call.Talkgroup = uint(v)
 	}
 
+	switch v := m["talkgroup_tag"].(type) {
+	case string:
+		call.talkgroupTag = v
+		call.talkgroupLabel = v
+	}
+
 	return nil
 }
diff --git a/server/unit.go b/server/unit.go
index 16278de..5fe1051 100644
--- a/server/unit.go
+++ b/server/unit.go
@@ -39,6 +39,23 @@ func (unit *Unit) FromMap(m map[string]interface{}) {
 
 type Units []Unit
 
+func (units *Units) Add(id uint, label string) *Units {
+	found := false
+
+	for _, u := range *units {
+		if u.Id == id {
+			found = true
+			break
+		}
+	}
+
+	if !found {
+		*units = append(*units, Unit{Id: id, Label: label})
+	}
+
+	return units
+}
+
 func (units *Units) FromJson(str string) error {
 	var v interface{}
 
@@ -67,6 +84,12 @@ func (units *Units) FromJson(str string) error {
 	return nil
 }
 
+func (u *Units) Merge(units *Units) {
+	for _, v := range *units {
+		u.Add(v.Id, v.Label)
+	}
+}
+
 func (units *Units) ToJson() (string, error) {
 	if b, err := json.Marshal(*units); err == nil {
 		return string(b), nil