Index: src/wp-admin/css/media.css
===================================================================
--- src/wp-admin/css/media.css	(revision 32469)
+++ src/wp-admin/css/media.css	(working copy)
@@ -566,9 +566,9 @@
 	font-size: 14px;
 }

-.media-frame.mode-grid .media-toolbar-secondary > .media-button {
-	margin-top: 10px;
-	margin-bottom: 10px;
+.media-frame.mode-grid.mode-edit .media-toolbar-secondary > .select-mode-toggle-button {
+	margin: 0 8px 0 0;
+	vertical-align: middle;
 }

 .media-frame.mode-grid .attachments-browser .bulk-select {
@@ -581,7 +581,7 @@
 }

 .media-frame.mode-grid .spinner {
-	margin-top: 15px;
+	margin-top: 16px;
 }

 .attachments-browser .media-toolbar-secondary > .media-button {
Index: src/wp-includes/js/media-grid.js
===================================================================
--- src/wp-includes/js/media-grid.js	(revision 32469)
+++ src/wp-includes/js/media-grid.js	(working copy)
@@ -279,6 +279,11 @@

 SelectModeToggle = Button.extend({
 	initialize: function() {
+
+		_.defaults( this.options, {
+			size: ''
+		});
+
 		Button.prototype.initialize.apply( this, arguments );
 		this.listenTo( this.controller, 'select:activate select:deactivate', this.toggleBulkEditHandler );
 		this.listenTo( this.controller, 'selection:action:done', this.back );
@@ -310,11 +315,13 @@

 		// TODO: the Frame should be doing all of this.
 		if ( this.controller.isModeActive( 'select' ) ) {
+			this.model.set( 'size', 'large' );
 			this.model.set( 'text', l10n.cancelSelection );
 			children.not( '.media-button' ).hide();
 			this.$el.show();
 			toolbar.$( '.delete-selected-button' ).removeClass( 'hidden' );
 		} else {
+			this.model.set( 'size', '' );
 			this.model.set( 'text', l10n.bulkSelect );
 			this.controller.content.get().$el.removeClass( 'fixed' );
 			toolbar.$el.css( 'width', '' );
Index: src/wp-includes/js/media/views/button/select-mode-toggle.js
===================================================================
--- src/wp-includes/js/media/views/button/select-mode-toggle.js	(revision 32469)
+++ src/wp-includes/js/media/views/button/select-mode-toggle.js	(working copy)
@@ -15,6 +15,11 @@

 SelectModeToggle = Button.extend({
 	initialize: function() {
+
+		_.defaults( this.options, {
+			size: ''
+		});
+
 		Button.prototype.initialize.apply( this, arguments );
 		this.listenTo( this.controller, 'select:activate select:deactivate', this.toggleBulkEditHandler );
 		this.listenTo( this.controller, 'selection:action:done', this.back );
@@ -46,11 +51,13 @@

 		// TODO: the Frame should be doing all of this.
 		if ( this.controller.isModeActive( 'select' ) ) {
+			this.model.set( 'size', 'large' );
 			this.model.set( 'text', l10n.cancelSelection );
 			children.not( '.media-button' ).hide();
 			this.$el.show();
 			toolbar.$( '.delete-selected-button' ).removeClass( 'hidden' );
 		} else {
+			this.model.set( 'size', '' );
 			this.model.set( 'text', l10n.bulkSelect );
 			this.controller.content.get().$el.removeClass( 'fixed' );
 			toolbar.$el.css( 'width', '' );