diff --git a/metrics/cloudwatch/cloudwatch.go b/metrics/cloudwatch/cloudwatch.go
index b9baa75..ca0c2bd 100644
--- a/metrics/cloudwatch/cloudwatch.go
+++ b/metrics/cloudwatch/cloudwatch.go
@@ -1,15 +1,14 @@
 package cloudwatch
 
 import (
+	"fmt"
 	"sync"
-
 	"time"
-
-	"fmt"
 
 	"github.com/aws/aws-sdk-go/aws"
 	"github.com/aws/aws-sdk-go/service/cloudwatch"
 	"github.com/aws/aws-sdk-go/service/cloudwatch/cloudwatchiface"
+
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/metrics"
 	"github.com/go-kit/kit/metrics/generic"
@@ -24,54 +23,54 @@
 	mtx        sync.RWMutex
 	namespace  string
 	svc        cloudwatchiface.CloudWatchAPI
-	counters   map[string]*Counter
-	gauges     map[string]*Gauge
-	histograms map[string]*Histogram
+	counters   map[string]*counter
+	gauges     map[string]*gauge
+	histograms map[string]*histogram
 	logger     log.Logger
 }
 
 // New returns a CloudWatch object that may be used to create metrics. Namespace is
 // applied to all created metrics and maps to the CloudWatch namespace.
 // Callers must ensure that regular calls to Send are performed, either manually or with one of the helper methods.
-func New(namespace string, logger log.Logger, svc cloudwatchiface.CloudWatchAPI) *CloudWatch {
+func New(namespace string, svc cloudwatchiface.CloudWatchAPI, logger log.Logger) *CloudWatch {
 	return &CloudWatch{
 		namespace:  namespace,
 		svc:        svc,
-		counters:   map[string]*Counter{},
-		gauges:     map[string]*Gauge{},
-		histograms: map[string]*Histogram{},
+		counters:   map[string]*counter{},
+		gauges:     map[string]*gauge{},
+		histograms: map[string]*histogram{},
 		logger:     logger,
 	}
 }
 
 // NewCounter returns a counter. Observations are aggregated and emitted once
 // per write invocation.
-func (cw *CloudWatch) NewCounter(name string) *Counter {
-	c := NewCounter(name)
+func (cw *CloudWatch) NewCounter(name string) metrics.Counter {
 	cw.mtx.Lock()
+	defer cw.mtx.Unlock()
+	c := &counter{c: generic.NewCounter(name)}
 	cw.counters[name] = c
-	cw.mtx.Unlock()
 	return c
 }
 
 // NewGauge returns a gauge. Observations are aggregated and emitted once per
 // write invocation.
-func (cw *CloudWatch) NewGauge(name string) *Gauge {
-	g := NewGauge(name)
+func (cw *CloudWatch) NewGauge(name string) metrics.Gauge {
 	cw.mtx.Lock()
+	defer cw.mtx.Unlock()
+	g := &gauge{g: generic.NewGauge(name)}
 	cw.gauges[name] = g
-	cw.mtx.Unlock()
 	return g
 }
 
 // NewHistogram returns a histogram. Observations are aggregated and emitted as
 // per-quantile gauges, once per write invocation. 50 is a good default value
 // for buckets.
-func (cw *CloudWatch) NewHistogram(name string, buckets int) *Histogram {
-	h := NewHistogram(name, buckets)
+func (cw *CloudWatch) NewHistogram(name string, buckets int) metrics.Histogram {
 	cw.mtx.Lock()
+	defer cw.mtx.Unlock()
+	h := &histogram{h: generic.NewHistogram(name, buckets)}
 	cw.histograms[name] = h
-	cw.mtx.Unlock()
 	return h
 }
 
@@ -87,14 +86,14 @@
 	}
 }
 
-// Send will fire an api request to CloudWatch with the latest stats for
-// all metrics.
+// Send will fire an API request to CloudWatch with the latest stats for
+// all metrics. It is preferred that the WriteLoop method is used.
 func (cw *CloudWatch) Send() error {
 	cw.mtx.RLock()
 	defer cw.mtx.RUnlock()
 	now := time.Now()
 
-	datums := []*cloudwatch.MetricDatum{}
+	var datums []*cloudwatch.MetricDatum
 
 	for name, c := range cw.counters {
 		datums = append(datums, &cloudwatch.MetricDatum{
@@ -140,77 +139,56 @@
 	return err
 }
 
-// Counter is a CloudWatch counter metric.
-type Counter struct {
+// counter is a CloudWatch counter metric.
+type counter struct {
 	c *generic.Counter
 }
 
-// NewCounter returns a new usable counter metric.
-func NewCounter(name string) *Counter {
-	return &Counter{
-		c: generic.NewCounter(name),
-	}
-}
-
 // With implements counter
-func (c *Counter) With(labelValues ...string) metrics.Counter {
+func (c *counter) With(labelValues ...string) metrics.Counter {
 	c.c = c.c.With(labelValues...).(*generic.Counter)
 	return c
 }
 
 // Add implements counter.
-func (c *Counter) Add(delta float64) {
+func (c *counter) Add(delta float64) {
 	c.c.Add(delta)
 }
 
-// Gauge is a CloudWatch gauge metric.
-type Gauge struct {
+// gauge is a CloudWatch gauge metric.
+type gauge struct {
 	g *generic.Gauge
 }
 
-// NewGauge returns a new usable gauge metric
-func NewGauge(name string) *Gauge {
-	return &Gauge{
-		g: generic.NewGauge(name),
-	}
-}
-
 // With implements gauge
-func (g *Gauge) With(labelValues ...string) metrics.Gauge {
+func (g *gauge) With(labelValues ...string) metrics.Gauge {
 	g.g = g.g.With(labelValues...).(*generic.Gauge)
 	return g
 }
 
 // Set implements gauge
-func (g *Gauge) Set(value float64) {
+func (g *gauge) Set(value float64) {
 	g.g.Set(value)
 }
 
 // Add implements gauge
-func (g *Gauge) Add(delta float64) {
+func (g *gauge) Add(delta float64) {
 	g.g.Add(delta)
 }
 
-// Histogram is a CloudWatch histogram metric
-type Histogram struct {
+// histogram is a CloudWatch histogram metric
+type histogram struct {
 	h *generic.Histogram
 }
 
-// NewHistogram returns a new usable histogram metric
-func NewHistogram(name string, buckets int) *Histogram {
-	return &Histogram{
-		h: generic.NewHistogram(name, buckets),
-	}
-}
-
 // With implements histogram
-func (h *Histogram) With(labelValues ...string) metrics.Histogram {
+func (h *histogram) With(labelValues ...string) metrics.Histogram {
 	h.h = h.h.With(labelValues...).(*generic.Histogram)
 	return h
 }
 
 // Observe implements histogram
-func (h *Histogram) Observe(value float64) {
+func (h *histogram) Observe(value float64) {
 	h.h.Observe(value)
 }
 
diff --git a/metrics/cloudwatch/cloudwatch_test.go b/metrics/cloudwatch/cloudwatch_test.go
index db68c38..c0cf1d0 100644
--- a/metrics/cloudwatch/cloudwatch_test.go
+++ b/metrics/cloudwatch/cloudwatch_test.go
@@ -2,14 +2,13 @@
 
 import (
 	"errors"
+	"fmt"
+	"sync"
 	"testing"
-
-	"sync"
-
-	"fmt"
 
 	"github.com/aws/aws-sdk-go/service/cloudwatch"
 	"github.com/aws/aws-sdk-go/service/cloudwatch/cloudwatchiface"
+
 	"github.com/go-kit/kit/log"
 	"github.com/go-kit/kit/metrics/teststat"
 )
@@ -65,7 +64,7 @@
 	namespace, name := "abc", "def"
 	label, value := "label", "value"
 	svc := newMockCloudWatch()
-	cw := New(namespace, log.NewNopLogger(), svc)
+	cw := New(namespace, svc, log.NewNopLogger())
 	counter := cw.NewCounter(name).With(label, value)
 	valuef := func() float64 {
 		err := cw.Send()
@@ -88,7 +87,7 @@
 	namespace, name := "abc", "def"
 	label, value := "label", "value"
 	svc := newMockCloudWatch()
-	cw := New(namespace, log.NewNopLogger(), svc)
+	cw := New(namespace, svc, log.NewNopLogger())
 	gauge := cw.NewGauge(name).With(label, value)
 	valuef := func() float64 {
 		err := cw.Send()
@@ -111,7 +110,7 @@
 	namespace, name := "abc", "def"
 	label, value := "label", "value"
 	svc := newMockCloudWatch()
-	cw := New(namespace, log.NewNopLogger(), svc)
+	cw := New(namespace, svc, log.NewNopLogger())
 	histogram := cw.NewHistogram(name, 50).With(label, value)
 	n50 := fmt.Sprintf("%s_50", name)
 	n90 := fmt.Sprintf("%s_90", name)