The OBA Rule book has a list of approved baseballs, see chart below. 
- Plan on 3 new balls for the first game of the tournament, on each diamond venue.
- Plan on 2 new balls for each game thereafter.
- Baseballs should be collected and inspected at the conclusion of each game. Some balls may be needed for playing at a future game.
- DO NOT USE BALLS
> designed for an older age level of play (e.g. bantam ball for Rookie);
> whose seams have loosened, frayed or been cut;
> leather has become rough and damaged;
> soaked wet
Section RP2.6-Approved Baseballs -- suggested for safe use for specific age divisions.
MAKE
|
MODEL
|
MANUFACTURER'S RECOMMENDED USE
|
Rawlings

|
TVB/TVB850
|
Indoor/Rally Cap
|
ROTB1/ROTB5
|
8U/9U/Indoor
|
45CC
|
Up to 9U
|
RTDC/RTD1/ROLB1X
|
Up to 13U
|
65CC
|
10U – 15U
|
80CC
|
10U – 18U
|
ROMLCAN**
|
All Divisions
|
CAN100HS
|
All Divisions
|
Louisville Slugger Canada

|
BB93
|
T-Ball
|
BB11
|
10U – 13U
|
BB12
|
14U - Senior
|
BB12-RL
|
16U to Senior
|
Mizuno

|
MB380
|
All Divisions
|
Silverstar Sports

|
818LS
|
8U – 13U
|
REV500
|
12U to Senior
|