This is Dubro's Tru-Spin Prop Balancer.

Features

Completely Adjustable Propeller Balancer
Precision-Machined Rotating Wheels to Assure Perfect Balance Easily
Unique Over/Under Set-Up Option Accomodates Even Large-Scale Props

Includes

One Tru Spin Prop Balancer

Comments

The following balancer shafts are available for this balancer;
#3381 DUBQ3381 6mm Shaft
#3384 DUBQ3384 8mmx1.25