The 250 series is the smallest series of components we offer. Based on 1/4 inch diameter tube, the 250 series is just the thing for rigging in tight places. Stop-motion animators, this is the series you've been asking for! All of the blocks are available in the 250 series; right angle blocks, parallel blocks, accessory mount blocks, linear and rotational blocks and more. As with all other Berkey System the 250 series can be interfaced with any of the other series of components through the use of bushings. Berkey System components are made from 6061 aluminum and are black anodized for durability. All Berkey System products are made in the USA and are covered by our Lifetime Warranty. See Terms and Conditions for details.