These are Becton Dickinson brand needles, most commonly used as play piercing needles... You can push these just about anywhere -- at your own risk of course. We recommend you don't. As far as we're officially concerned you should just look at them as pieces of industrial art.
These needles come in boxes of 100. They have luer-lock hubs. All are 1.5" long, except the 27ga, which come in a 1.25" length and 30ga which come in a 1" length.
Warning: Make sure needles are legal in your area before ordering. Pricing is subject to change and set by the manufacturer.