Please google "Tennis Battery Twist Ball Machine - Battery Powered Model" to find the exact model and retail price ($230 for a new one).

Bought 3-yrs ago to work on my 1HBH and my kid's strokes. Worked effectively.

Mine (in very good condition) $130 for sale.

Features
* Shoots a ball every 5 seconds
* Ball arc can be adjusted from 12' to 20' in length
* Unique spiral design holds up to 28 balls
* Adjustable range makes it practical for use in driveways, backyards, and even basements
* Lightweight for easy transport

Specifications
* Ball capacity: 28 balls
* Maximum Ball Ejection: 10' to 20' toss
* Ball Feed Rate: 5 seconds
* Playing Time: 5-10 hours, typical
* Weight: 11 lbs
* Runs on 6 "D" batteries (not included)