The Tactical Frog FX-Diving V4 automatic and FX-Diving solar chronograph share titanium cases and fixed strap bars, but they are different watches. Choose between the movement and timing functions first, then compare crystal-inclusive thickness and strap compatibility.
This is a comparison of two current Watchdives listings, not a hands-on diving test. Specifications, available configurations and USD prices were checked on October 7, 2026. Both had purchasable configurations at $199 before shipping, taxes and import charges.
V4 automatic versus solar chronograph
| Feature | FX-Diving V4 automatic | FX-Diving solar chronograph |
|---|---|---|
| Listed movement | Hangzhou 2565 automatic | Japan VS75B solar quartz chronograph |
| Power | Mechanical automatic movement | Light-charged rechargeable cell |
| Case material | Titanium | Titanium |
| Diameter without crown | 42mm | 42mm |
| Overall width including crown | 51mm | 50mm |
| Thickness including crystal | 13.31mm | 14.2mm |
| Strap attachment | Fixed bars, 22mm fabric strap | Fixed bars, 22mm fabric strap |
| Bezel description | Bidirectional titanium bezel with ceramic insert and 60-minute navigation scale | Bidirectional rotating ceramic bezel |
| Crystal / listed water resistance | Sapphire with AR / 200m | Sapphire with AR / 200m |
| Checked available watch price | $199 | $199 |
The 51mm and 50mm widths include the crown. They are not lug-to-lug measurements. Neither current listing provides a separately identified lug-to-lug figure, so do not use those widths to promise fit across the top of your wrist. Both thickness figures include the crystal, making their stated basis clearer than an unlabeled case-height comparison.
Choose automatic or solar by ownership and function
Choose the V4 if you want the mechanically powered automatic model and its simpler main time display. Its current listing identifies Hangzhou 2565. Older FX-Diving articles and owner discussions may describe NH35 versions; that is not a reason to substitute NH35 specifications into the current V4 listing.
Choose the solar model if you want quartz regulation, light charging and chronograph functionality. It identifies VS75B. Our VS75 movement guide provides background on the solar family; follow the exact watch instructions for charging and operation. Do not assume the movement’s published reserve or charging conditions are a measured result for every complete watch.
The checked watch-only prices were equal, so paying more is not the deciding factor in this pair. V4 had Black - Date, Blue - Date, Blue dial - blue bezel, Black dial - black bezel and Gradient Red options available. Solar had Blue and White options available. Confirm the calendar layout and exact configuration on the product page.
Fixed strap bars change what you can attach
Both listings specify fixed strap bars and a 22mm fabric strap with a self-gripping fastening system and titanium buckle. Matching “22mm” alone does not prove that a replacement will attach. A conventional two-piece strap designed around removable spring bars should not be assumed compatible with a closed fixed-bar case.
Confirm that the replacement strap’s construction can pass around or open around the fixed bars, as well as its width, thickness and closure. Do not buy a standard bracelet or a curved-end two-piece strap on width alone. If you want those attachment options, compare a watch with conventional removable bars instead.
Bidirectional bezels are a different timing choice
Both Tactical Frog listings specify bidirectional rotation. The V4 text additionally identifies a 60-minute navigation scale; the solar listing does not establish the same scale configuration, so inspect its bezel markings separately. Neither should be described here as a conventional unidirectional elapsed-time bezel.
For context, TUDOR’s original French Navy Pelagos FXD page explains fixed bars and a bidirectional countdown bezel used for underwater navigation. That explains why fixed-bar watch discussions often involve this bezel format. It does not establish shared construction, certification, military use or performance for Tactical Frog. Other FXD references also use different bezels, so identify the exact model rather than applying one family-wide rule.
The two Tactical Frog listings state 200m water resistance. That rating alone does not establish ISO dive-watch certification or make this buyer comparison an operational diving instruction. Follow the exact watch’s use and service guidance.
Historical video reference
The brand’s September 2023 V4-with-date demonstration is available on YouTube and its original brand article. It is historical footage, not verification of the current movement, dial options, price or stock. Use today’s linked product listing for your order.
Which one should you order?
Choose V4 for the automatic configuration and its lower listed crystal-inclusive height. Choose the solar chronograph for light charging and stopwatch functionality. Choose neither if fixed bars conflict with the bracelet or two-piece strap you intend to use. Confirm fit, dial and delivered price before ordering.
For steel-bracelet solar alternatives, read our four-model Tactical Frog solar chronograph comparison. For other titanium options, see our titanium dive-watch guide, or browse the Tactical Frog collection.
