diff --git a/README.md b/README.md
index 340b429..9070e17 100644
--- a/README.md
+++ b/README.md
@@ -36,7 +36,7 @@ docker run -d -e "CI_SERVER_URL=https://gitlab.com/" \
    -e REGISTRATION_TOKEN="$REGISTRATION_TOKEN" \
    -e ADMIN_TOKEN="$ADMIN_TOKEN" \
    -e PROJECTS_TO_REGISTER="$PROJECTS_TO_REGISTER" \
-   -e LOCKED_MODE="false" \
+   -e REGISTER_LOCKED="false" \
    --name gitlab-runner-testing \
    -v /var/run/docker.sock:/var/run/docker.sock \
    flakm/gitlab-runner-auto-register:latest
@@ -63,17 +63,24 @@ docker exec -i gitlab-runner gitlab-runner register
 
 # Environment Variables
 
-| Property              |  Description                                                                                                           | Default value                   | Required      |
-| --------------------  | -----------------------------------------------------------------------------------------------------------------------| ------------------------------- | ------------- |
-|`CI_SERVER_URL`        |  url of gitlab instance                                                                                                |                                 | true          |
-|`REGISTRATION_TOKEN`   |  /settings/ci_cd tab of your project                                                                                   |                                 | true          |
-|`PRIVILIGED_MODE`      |  should you need to run in priviliged mode set to true (otherwise defaults to false)                                   | false                           | false         |           
-|`LOCKED_MODE`          |  should this runner be locked to this project or not                                                                   | true                            | false         |
-|`ADMIN_TOKEN`          |  access token with admin privilages (if specified runner will be registered for projects`PROJECTS_TO_REGISTER`)        |                                 | false         |
-|`PROJECTS_TO_REGISTER` |  project ids seperated by `;`                                                                                          |                                 | false         |
-|`CUSTOM_RUNNER_NAME`   |  runner's description                                                                                                  | `$HOSTNAME`                     | false         |
-
-For more information about the the environment variables execute `gitlab-runner register --help` inside docker
+| Property              |  Description                                                                                                                             | Default value                   | Required      |
+| --------------------  | -----------------------------------------------------------------------------------------------------------------------------------------| ------------------------------- | ------------- |
+|`CI_SERVER_URL`        |  url of gitlab instance                                                                                                                  |                                 | true          |
+|`REGISTRATION_TOKEN`   |  /settings/ci_cd tab of your project                                                                                                     |                                 | true          |
+|`DOCKER_PRIVILEGED`    |  should you need to run in priviliged mode set to true (otherwise defaults to false)                                                     | false                           | false         |           
+|`REGISTER_LOCKED`      |  should this runner be locked to this project or not                                                                                     | true                            | false         |
+|`ADMIN_TOKEN`          |  access token with admin privilages (if specified runner will be registered for projects`PROJECTS_TO_REGISTER`)                          |                                 | false         |
+|`PROJECTS_TO_REGISTER` |  project ids seperated by `;`                                                                                                            |                                 | false         |
+|`CUSTOM_RUNNER_NAME`   |  runner's description                                                                                                                    | `$HOSTNAME`                     | false         |
+|`DOCKER_VOLUMES`       |  volume mounted by this runner                                                                                                           |                                 | false         |
+|`DOCKER_IMAGE`         |  docker image to use                                                                                                                     | docker:18.01.0-ce               | true          |
+|`REGISTER_EXTRA_ARGS`  |  can contain extra arguments for running `gitlab-runner register`. <br>Can be used for example to specify multiple --docker-volumes args |                                 | false         |
+
+For more information about the the environment variables execute: 
+```
+docker run --rm --entrypoint "/usr/bin/gitlab-runner" flakm/gitlab-runner-auto-register:latest register --help
+``` 
+
 
 
 # Inspiration
diff --git a/entrypoint.sh b/entrypoint.sh
index ce3710e..7764937 100755
--- a/entrypoint.sh
+++ b/entrypoint.sh
@@ -4,19 +4,15 @@ if [ -z "$CI_SERVER_URL" ]; then
   CI_SERVER_URL="https://gitlab.com/"
 fi
 
+if [ -z "$DOCKER_IMAGE" ]; then
+  export DOCKER_IMAGE=docker:18.01.0-ce
+fi
+
 if [ -z "$REGISTRATION_TOKEN" ]; then
   echo "ERROR: Env REGISTRATION_TOKEN not set!"
   exit 1
 fi
 
-if [ "$PRIVILIGED_MODE" != "true" ]; then
-  PRIVILIGED_MODE="false"
-fi
-
-if [ "$LOCKED_MODE" != "true" ]; then
-  LOCKED_MODE="true"
-fi
-
 if [ "$ADMIN_TOKEN" != "" ]; then
   REGISTER_OTHER_PROJECTS="true"
   PROJECTS_STRING="$PROJECTS_TO_REGISTER"
@@ -55,7 +51,7 @@ trap "gitlab-runner stop" SIGTERM
 echo "===> Running gitlab-runner register..."
 export REGISTER_NON_INTERACTIVE=true
 
-gitlab-runner register --executor=docker --locked=$LOCKED_MODE --docker-image=docker:latest  --docker-privileged=$PRIVILIGED_MODE --docker-volumes=/var/run/docker.sock:/var/run/docker.sock
+gitlab-runner register --executor=docker $REGISTER_EXTRA_ARGS
 if [ $? -gt 0 ]; then
   echo "===> ERROR: Registration failed!"
   exit 1