[Material]:This dovetail plate is made of metal,which can be used for long term [Narrow Rail Size]:The narrow rail measures 43.4mm,allowing for quick disassembly/assembly of the main mirror tube [Convenient Design]:During the locking process,the screw head can be pulled out to change the direction of the wrench.Additionally,an M8 screw hole is available for installing a counterweight if needed [Product for Dimensions]:Guide star dovetail mounting plate are 205x102mm,making it compact and easy to handle [Function]:Wide to narrow dovetail adapter plate designed to convert wide rail astronomical telescopes into narrow rails for use with equatorial mounts