Quality replacement bass machines for 2+2 head stocks. Button type is known as "Whale Tail". This type of machine head is often found on modern bass guitars.
Not what you want? If you don't see it here we may still be able to help so get in touch and we'll do what we can. If you really need to find that part or accessory now, why not visit our old guitar parts site at www.guitar-parts-and-spares-uk.com or if you prefer, visit these Amazon Guitar Links and see if they have what you want.