Hand Injectors with Locking Pins. 2" diameter injectors 8oz Injector  = $155.99 12oz Injector=$169.99 16oz Injector = $175.99 20oz Injector = $185.99 Dual Kit only = $115.99 Dual 8oz Injector = $369.99.99 Dual 12oz injector = $389.99 includes 2 injectors and kit Dual 16oz injector=$409.99 includes 2 injectors and kit Dual 20oz injector=$429.99 includes 2 injectors and kit All injectors Comes with 2 O-Rings