There are 9 Spider-Man 2 Prowler Stashes scattered around New York that give Rare Tech and XP, plus a final reward for completion.
Marvel's Spider-Man 2: Prowler in Training
Spider-Man 2 Prowler Stashes - All Locations Guide - GameSpot
Spider-Man 2 Prowler Stashes - All Locations Guide - GameSpot
Spider-Man 2 walkthrough, tips and tricks
Prowler Stashes: Marvel's Spider-Man 2: All Prowler Stashes and how to complete
All Prowler Stash locations in Spider-Man 2 - Dot Esports
Spider-Man 2 Interactive Maps and Locations Guide - News
Spider-Man 2: All Prowler Stash Locations and Solutions
Marvel's Spider-Man 2: Every Collectible and Activity (& Where to Find Them)
Prowler Stashes: Marvel's Spider-Man 2: All Prowler Stashes and how to complete
Astoria Prowler Stash - Marvel's Spider-Man 2 Guide - IGN
All Prowler Stash Locations (& Solutions) In Marvel's Spider-Man 2
All Prowler Stash Locations: Spider-Man 2 - GameRiv
Spider Man 2 Downtown Brooklyn Prowler Stash Solution - Airwaves
Spider-Man 2 All Prowler Stash Locations