This is the most popular middle gear For many kavo Contra Angle models
The Following model just for your reference:
Kavo 68LH, 79, 80, 54B, 31, 31A, 68CD, 68CN, 68CDN, 31F, 52F, 68F, 79F, 80F, 52G, 68G, 68GD, 79G, 80G, 52GDN, 68GDN, 68LD, 80LD, 52LDN, 68LDN
MK-DENT LS9011