The DW-5600 has kept the same square outline since 1983, and now G-Shock has made it small enough for a finger. The DWN-5600 is the brand’s first ring. A resin band with molded segments carries the four-button LCD module and the PROTECTION and SHOCK RESIST markings and the 20-bar water resistance of the full-size model. Someone who already wears the watch will want this and feel a little odd about it. It comes in black, yellow and red, each with the full-size dial graphics at ring scale. It costs $110.