diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerConfiguration.java b/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerConfiguration.java
index 6e465fd5e..b70c747ca 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerConfiguration.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/WhisperServerConfiguration.java
@@ -7,9 +7,11 @@ package org.whispersystems.textsecuregcm;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import io.dropwizard.Configuration;
 import java.util.HashMap;
+import java.util.HashSet;
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.Set;
 import javax.validation.Valid;
 import javax.validation.constraints.NotNull;
 import org.whispersystems.textsecuregcm.configuration.AccountDatabaseCrawlerConfiguration;
@@ -45,7 +47,6 @@ import org.whispersystems.textsecuregcm.configuration.SecureValueRecovery2Config
 import org.whispersystems.textsecuregcm.configuration.SpamFilterConfiguration;
 import org.whispersystems.textsecuregcm.configuration.StripeConfiguration;
 import org.whispersystems.textsecuregcm.configuration.SubscriptionConfiguration;
-import org.whispersystems.textsecuregcm.configuration.TestDeviceConfiguration;
 import org.whispersystems.textsecuregcm.configuration.UnidentifiedDeliveryConfiguration;
 import org.whispersystems.textsecuregcm.configuration.ZkConfig;
 import org.whispersystems.textsecuregcm.limits.RateLimiterConfig;
@@ -152,7 +153,7 @@ public class WhisperServerConfiguration extends Configuration {
   @Valid
   @NotNull
   @JsonProperty
-  private List<TestDeviceConfiguration> testDevices = new LinkedList<>();
+  private Set<String> testDevices = new HashSet<>();
 
   @Valid
   @NotNull
@@ -371,15 +372,8 @@ public class WhisperServerConfiguration extends Configuration {
     return unidentifiedDelivery;
   }
 
-  public Map<String, Integer> getTestDevices() {
-    Map<String, Integer> results = new HashMap<>();
-
-    for (TestDeviceConfiguration testDeviceConfiguration : testDevices) {
-      results.put(testDeviceConfiguration.getNumber(),
-                  testDeviceConfiguration.getCode());
-    }
-
-    return results;
+  public Set<String> getTestDevices() {
+    return testDevices;
   }
 
   public Map<String, Integer> getMaxDevices() {
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/captcha/RegistrationCaptchaManager.java b/service/src/main/java/org/whispersystems/textsecuregcm/captcha/RegistrationCaptchaManager.java
index 044c70048..471fb66fa 100644
--- a/service/src/main/java/org/whispersystems/textsecuregcm/captcha/RegistrationCaptchaManager.java
+++ b/service/src/main/java/org/whispersystems/textsecuregcm/captcha/RegistrationCaptchaManager.java
@@ -11,8 +11,9 @@ import com.codahale.metrics.Meter;
 import com.codahale.metrics.MetricRegistry;
 import com.codahale.metrics.SharedMetricRegistries;
 import java.io.IOException;
-import java.util.Map;
 import java.util.Optional;
+import java.util.Set;
+
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;
 import org.whispersystems.textsecuregcm.configuration.dynamic.DynamicCaptchaConfiguration;
@@ -37,12 +38,12 @@ public class RegistrationCaptchaManager {
 
   private final CaptchaChecker captchaChecker;
   private final RateLimiters rateLimiters;
-  private final Map<String, Integer> testDevices;
+  private final Set<String> testDevices;
   private final DynamicConfigurationManager<DynamicConfiguration> dynamicConfigurationManager;
 
 
   public RegistrationCaptchaManager(final CaptchaChecker captchaChecker, final RateLimiters rateLimiters,
-      final Map<String, Integer> testDevices,
+      final Set<String> testDevices,
       final DynamicConfigurationManager<DynamicConfiguration> dynamicConfigurationManager) {
     this.captchaChecker = captchaChecker;
     this.rateLimiters = rateLimiters;
@@ -60,7 +61,7 @@ public class RegistrationCaptchaManager {
 
   public boolean requiresCaptcha(final String number, final String forwardedFor, String sourceHost,
       final boolean pushChallengeMatch) {
-    if (testDevices.containsKey(number)) {
+    if (testDevices.contains(number)) {
       return false;
     }
 
diff --git a/service/src/main/java/org/whispersystems/textsecuregcm/configuration/TestDeviceConfiguration.java b/service/src/main/java/org/whispersystems/textsecuregcm/configuration/TestDeviceConfiguration.java
deleted file mode 100644
index 82b2fbf35..000000000
--- a/service/src/main/java/org/whispersystems/textsecuregcm/configuration/TestDeviceConfiguration.java
+++ /dev/null
@@ -1,29 +0,0 @@
-/*
- * Copyright 2013-2020 Signal Messenger, LLC
- * SPDX-License-Identifier: AGPL-3.0-only
- */
-
-package org.whispersystems.textsecuregcm.configuration;
-
-import com.fasterxml.jackson.annotation.JsonProperty;
-import javax.validation.constraints.NotEmpty;
-import javax.validation.constraints.NotNull;
-
-public class TestDeviceConfiguration {
-
-  @JsonProperty
-  @NotEmpty
-  private String number;
-
-  @JsonProperty
-  @NotNull
-  private int code;
-
-  public String getNumber() {
-    return number;
-  }
-
-  public int getCode() {
-    return code;
-  }
-}
diff --git a/service/src/test/java/org/whispersystems/textsecuregcm/controllers/AccountControllerTest.java b/service/src/test/java/org/whispersystems/textsecuregcm/controllers/AccountControllerTest.java
index 32267e238..a36476f7f 100644
--- a/service/src/test/java/org/whispersystems/textsecuregcm/controllers/AccountControllerTest.java
+++ b/service/src/test/java/org/whispersystems/textsecuregcm/controllers/AccountControllerTest.java
@@ -221,7 +221,7 @@ class AccountControllerTest {
       accountsManager, clientPresenceManager, svr1CredentialsGenerator, svr2CredentialsGenerator, registrationRecoveryPasswordsManager,
       pushNotificationManager, rateLimiters);
   private static final RegistrationCaptchaManager registrationCaptchaManager = new RegistrationCaptchaManager(
-      captchaChecker, rateLimiters, Map.of(TEST_NUMBER, 123456), dynamicConfigurationManager);
+      captchaChecker, rateLimiters, Set.of(TEST_NUMBER), dynamicConfigurationManager);
 
   private static final ResourceExtension resources = ResourceExtension.builder()
       .addProvider(AuthHelper.getAuthFilter())