Andro Rasanter R37

The number refers to its soft 37-degree sponge, not to irreversible deformation or an industrial material rating. The R series is tuned for rotation, using topsheet geometry designed to increase ball contact and spin.

Yes, its soft sponge activates with compact strokes, making it popular for controlled backhand topspins, blocks, and developing technique. Powerful players may bottom it out during hard counterloops and prefer R42 or R47.

Ultramax uses a roughly 2.3mm sponge made possible by a thinner topsheet. It provides more rebound and speed than the thinner 1.7mm or 2.0mm options, with less margin for passive control.

Andro designed the Rasanter family around the larger plastic ball, with extra sponge volume intended to recover speed and spin. R37 generates a curved topspin trajectory at moderate swing speed, but it is not as direct or powerful as the harder R47.