Compatible with models:

Vintage Vespa (Largeframe / Wideframe / Smallframe):
Vespa 125 (VNB3T, VNB4T, VNB5T, VNB6T, VGL1T, VGLA1T, VGLB1T)
Vespa 150 (VB1T, VBA1T, VBB1T, VBB2T)
Vespa 150 GS (VS2T, VS3T, VS4T, VS5T)
Vespa 160 GS / 180 GS (VSB1T, VSB2T)
Often also compatible/adaptable for the 50 series (N, L, R, Special) and other vintage models with 21–22 mm tubular handlebars.

Piaggio Ape and Pentarò:
Ape 175 / Ape D 500 (AD1T, AD2T)
Ape AC (AC1T, AC2T, AC3T, AC4T)
Ape AE / Ape E 400 (AE01T, AE02T, AE1T, AE2T, AE3T)
Ape 550 MP (MPA1T)
Ape Pentarò (APA1T, APC1T, APC2T)