Item Number: DUB672 For those requiring a really heavy duty servo arm, the Dubro"Super Strength" arms will fit the bill.Features: White composite plastic servo arms.Includes: 2 each of short, medium and long servo arms the extend inone direction from the servo center. Also has two long armsthat extend in two opposing directions from the servo center.Specs: Short : Mounting holes at: 12, 15 and 18mm. Total length-23mm.Medium: Mounting holes at: 15, 19, 22 and 25mm. Total length-30mm.Long : Mounting holes at: 23, 25, 28 and 32mm. Total length-36mm.Dual : Mounting holes at: 15, 19, 23 and 26mm. Total length-28mm.* All measurements are from the center of the arm.* The dual is only from one side to center. Actual overall length- 56mm.* Fits the HI-TEC, HOBBICO, and TOWER servos with splined output shafts.