Mag Base Indicator Holder with Articulating Arms Specifications include... Base Dimensions 4.61" L x 1.98" W x 2.19" HT 27" Arm Length 286 lbs Magnetic Pull Features include... Arm has 3 articulating joints that can be locked with a single hand knob. Use with 3/8" and 8mm stem diameter indicators. Magnetic bases have On/Off switch. UPS Ground shipping ONLY