Excalibur and Easton teamed up to develop Quill Illuminated-Nock Bolts for use with micro crossbows. 2 offset vanes stabilize the bolt. Proven effective with micro crossbows. Illuminated nocks help you follow the bolts path and easily locate bolts. Per 3. Length: 16.5. Cancer and Reproductive Harm- www.P65Warnings.ca.gov. Type: Carbon Bolts.