diff --git a/ui/src/shared/components/OptIn.js b/ui/src/shared/components/OptIn.tsx
similarity index 64%
rename from ui/src/shared/components/OptIn.js
rename to ui/src/shared/components/OptIn.tsx
index 2160648e7e..50c40ec140 100644
--- a/ui/src/shared/components/OptIn.js
+++ b/ui/src/shared/components/OptIn.tsx
@@ -1,14 +1,42 @@
-import React, {Component} from 'react'
-import PropTypes from 'prop-types'
+import React, {Component, ChangeEvent, KeyboardEvent, MouseEvent} from 'react'
 import classnames from 'classnames'
 
 import uuid from 'uuid'
 
-import ClickOutsideInput from 'shared/components/ClickOutsideInput'
+import ClickOutsideInput from 'src/shared/components/ClickOutsideInput'
 import {ErrorHandling} from 'src/shared/decorators/errors'
 
+interface Props {
+  min: string
+  fixedPlaceholder: string
+  fixedValue: string
+  customPlaceholder: string
+  customValue: string
+  onSetValue: (value: string) => void
+  type: string | number
+}
+
+interface State {
+  fixedValue: string
+  customValue: string
+  useCustomValue: boolean
+}
+
 @ErrorHandling
-class OptIn extends Component {
+export default class OptIn extends Component<Props, State> {
+  public static defaultProps: Partial<Props> = {
+    fixedValue: '',
+    customPlaceholder: 'Custom Value',
+    fixedPlaceholder: 'auto',
+    customValue: '',
+  }
+
+  private id: string
+  private isCustomValueInputFocused: boolean
+  private grooveKnobContainer: HTMLElement
+  private grooveKnob: HTMLElement
+  private customValueInput: HTMLInputElement
+
   constructor(props) {
     super(props)
 
@@ -24,84 +52,7 @@ class OptIn extends Component {
     this.isCustomValueInputFocused = false
   }
 
-  useFixedValue = () => {
-    this.setState({useCustomValue: false, customValue: ''}, () =>
-      this.setValue()
-    )
-  }
-
-  useCustomValue = () => {
-    this.setState({useCustomValue: true}, () => this.setValue())
-  }
-
-  handleClickToggle = () => {
-    const useCustomValueNext = !this.state.useCustomValue
-    if (useCustomValueNext) {
-      this.useCustomValue()
-      this.customValueInput.focus()
-    } else {
-      this.useFixedValue()
-    }
-  }
-
-  handleFocusCustomValueInput = () => {
-    this.isCustomValueInputFocused = true
-    this.useCustomValue()
-  }
-
-  handleChangeCustomValue = e => {
-    this.setCustomValue(e.target.value)
-  }
-
-  handleKeyDownCustomValueInput = e => {
-    if (e.key === 'Enter' || e.key === 'Tab') {
-      if (e.key === 'Enter') {
-        this.customValueInput.blur()
-      }
-      this.considerResetCustomValue()
-    }
-  }
-
-  handleClickOutsideInput = e => {
-    if (
-      e.target.id !== this.grooveKnob.id &&
-      e.target.id !== this.grooveKnobContainer.id &&
-      this.isCustomValueInputFocused
-    ) {
-      this.considerResetCustomValue()
-    }
-  }
-
-  considerResetCustomValue = () => {
-    const customValue = this.customValueInput.value.trim()
-
-    this.setState({customValue})
-
-    if (customValue === '') {
-      this.useFixedValue()
-    }
-
-    this.isCustomValueInputFocused = false
-  }
-
-  setCustomValue = value => {
-    this.setState({customValue: value}, this.setValue)
-  }
-
-  setValue = () => {
-    const {onSetValue} = this.props
-    const {useCustomValue, fixedValue, customValue} = this.state
-
-    if (useCustomValue) {
-      onSetValue(customValue)
-    } else {
-      onSetValue(fixedValue)
-    }
-  }
-
-  handleInputRef = el => (this.customValueInput = el)
-
-  render() {
+  public render() {
     const {fixedPlaceholder, customPlaceholder, type, min} = this.props
     const {useCustomValue, customValue} = this.state
 
@@ -143,25 +94,86 @@ class OptIn extends Component {
       </div>
     )
   }
+
+  private useFixedValue = (): void => {
+    this.setState({useCustomValue: false, customValue: ''}, () =>
+      this.setValue()
+    )
+  }
+
+  private useCustomValue = (): void => {
+    this.setState({useCustomValue: true}, () => this.setValue())
+  }
+
+  private handleClickToggle = (): void => {
+    const useCustomValueNext = !this.state.useCustomValue
+    if (useCustomValueNext) {
+      this.useCustomValue()
+      this.customValueInput.focus()
+    } else {
+      this.useFixedValue()
+    }
+  }
+
+  private handleFocusCustomValueInput = (): void => {
+    this.isCustomValueInputFocused = true
+    this.useCustomValue()
+  }
+
+  private handleChangeCustomValue = (
+    e: ChangeEvent<HTMLInputElement>
+  ): void => {
+    this.setCustomValue(e.target.value)
+  }
+
+  private handleKeyDownCustomValueInput = (
+    e: KeyboardEvent<HTMLInputElement>
+  ): void => {
+    if (e.key === 'Enter' || e.key === 'Tab') {
+      if (e.key === 'Enter') {
+        this.customValueInput.blur()
+      }
+      this.considerResetCustomValue()
+    }
+  }
+
+  private handleClickOutsideInput = (e: MouseEvent<HTMLElement>): void => {
+    if (
+      e.currentTarget.id !== this.grooveKnob.id &&
+      e.currentTarget.id !== this.grooveKnobContainer.id &&
+      this.isCustomValueInputFocused
+    ) {
+      this.considerResetCustomValue()
+    }
+  }
+
+  private considerResetCustomValue = (): void => {
+    const customValue = this.customValueInput.value.trim()
+
+    this.setState({customValue})
+
+    if (customValue === '') {
+      this.useFixedValue()
+    }
+
+    this.isCustomValueInputFocused = false
+  }
+
+  private setCustomValue = (value): void => {
+    this.setState({customValue: value}, this.setValue)
+  }
+
+  private setValue = (): void => {
+    const {onSetValue} = this.props
+    const {useCustomValue, fixedValue, customValue} = this.state
+
+    if (useCustomValue) {
+      onSetValue(customValue)
+    } else {
+      onSetValue(fixedValue)
+    }
+  }
+
+  private handleInputRef = (el: HTMLInputElement) =>
+    (this.customValueInput = el)
 }
-
-OptIn.defaultProps = {
-  fixedValue: '',
-  customPlaceholder: 'Custom Value',
-  fixedPlaceholder: 'auto',
-  customValue: '',
-}
-
-const {func, oneOf, string} = PropTypes
-
-OptIn.propTypes = {
-  min: string,
-  fixedPlaceholder: string,
-  fixedValue: string,
-  customPlaceholder: string,
-  customValue: string,
-  onSetValue: func.isRequired,
-  type: oneOf(['text', 'number']),
-}
-
-export default OptIn