Photo and specs courtesy of Brunswick. Reproduced with credit to the maker.

How it moves

Arcing turn (symmetric core). Dotted is skid, then the turn, then the roll into the pocket. Estimated from the coverstock, finish, core, and differential for a right-handed bowler with medium revs on a house shot. Lane conditions, speed, and layout move all of this.

Brunswick

Rhino Charcoal/Silver/Violet

Name: Brunswick Rhino Charcoal/Silver/Violet
Brand: Brunswick

Discontinued

Hook potential5 (est.)5 of 10, estimated

How much the ball wants to hook, 1 (straight, a spare ball) to 10 (the strongest oil-eaters). The maker publishes no number for this ball, so this is estimated from the coverstock, core, finish, and differential.

Coverstock: R-16; Reactive pearl
Core: Light Bulb
Factory finish: 500 Siaair / Crown Factory Compound / Crown Factory Polish
Color: Charcoal / Silver / Violet
Released: Not listed
USBC: Approved 2019-04-16

Weights and specs

Weight	RG	Differential	Int. diff
10 lb	2.80	0.002	—
11 lb	2.77	0.002	—
12 lb	2.58	0.030	—
13 lb	2.56	0.030	—
14 lb	2.54	0.030	—
15 lb	2.52	0.030	—
16 lb	2.51	0.030	—

Surface

Coarse grit

Coarse and fine

Fine grit or polish

500 Siaair / Crown Factory Compound / Crown Factory Polish. Skims the oil and saves its energy for the dry part of the lane: longer skid, later and sharper hook. Polished and pearl balls. Surface changes over games, and a pro shop can take any ball either way with a pad.